diff --git a/DATA_STRUCTURE.md b/DATA_STRUCTURE.md
index ce36205..f972ead 100644
--- a/DATA_STRUCTURE.md
+++ b/DATA_STRUCTURE.md
@@ -1,4 +1,65 @@
-# Example Data Structure for Axia4
+# Data Architecture for Axia4
+
+Axia4 uses a **SQLite database** (`/DATA/axia4.sqlite`) for all structured data, with the
+filesystem reserved for binary assets (photos, uploaded files, project documents).
+
+## Database (`/DATA/axia4.sqlite`)
+
+The schema is defined in `public_html/_incl/migrations/001_initial_schema.sql` and
+applied automatically on first boot via `db.php`.
+
+| Table                | Replaces                                          |
+|----------------------|---------------------------------------------------|
+| `config`             | `/DATA/AuthConfig.json`                           |
+| `users`              | `/DATA/Usuarios/*.json`                           |
+| `invitations`        | `/DATA/Invitaciones_de_usuarios.json`             |
+| `centros`            | Directory existence at `.../Centros/{id}/`        |
+| `user_centros`       | `entreaulas.centro` + `entreaulas.aulas` in users |
+| `aularios`           | `.../Aularios/{id}.json`                          |
+| `supercafe_menu`     | `.../SuperCafe/Menu.json`                         |
+| `supercafe_orders`   | `.../SuperCafe/Comandas/*.json`                   |
+| `comedor_menu_types` | `.../Comedor-MenuTypes.json`                      |
+| `comedor_entries`    | `.../Comedor/{ym}/{day}/_datos.json`              |
+| `club_events`        | `/DATA/club/IMG/{date}/data.json`                 |
+| `club_config`        | `/DATA/club/config.json`                          |
+
+## Migrations
+
+Migrations live in `public_html/_incl/migrations/`:
+
+- `001_initial_schema.sql` — DDL for all tables.
+- `002_import_json.php`    — One-time importer: reads existing JSON files and
+  inserts them into the database. Run automatically on first boot if JSON files
+  exist and the DB is empty.
+
+## Filesystem (binary / large assets)
+
+```
+DATA/
+└── entreaulas/
+    └── Centros/
+        └── {centro_id}/
+            ├── Aularios/
+            │   └── {aulario_id}/
+            │       ├── Alumnos/            # Student photo directories
+            │       │   └── {alumno}/photo.jpg
+            │       ├── Comedor/{ym}/{day}/  # Comedor pictogram images
+            │       └── Proyectos/          # Project binary files
+            └── Panel/
+                └── Actividades/{name}/photo.jpg   # Activity photos
+└── club/
+    └── IMG/{date}/          # Club event photos (still on filesystem)
+```
+
+## Multi-Tenant Support
+
+A user can belong to **multiple centros** (organizations).  The active centro
+is stored in `$_SESSION['active_centro']` and can be switched at any time via
+`POST /_incl/switch_tenant.php`.
+
+The account page (`/account/`) shows all assigned organizations and lets the
+user switch between them.
+
 
 This directory contains example data files that demonstrate the structure needed for the Axia4 application.
 
diff --git a/Dockerfile b/Dockerfile
index a7d1076..659d075 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -8,7 +8,7 @@ FROM dunglas/frankenphp
 #     && rm -rf /var/lib/apt/lists/*
 
 # Configure PHP extensions
-RUN install-php-extensions gd opcache
+RUN install-php-extensions gd opcache pdo pdo_sqlite
 
 # Set working directory
 WORKDIR /var/www/html
diff --git a/Dockerfile.dev b/Dockerfile.dev
index 2b975b6..10a1f71 100644
--- a/Dockerfile.dev
+++ b/Dockerfile.dev
@@ -8,7 +8,7 @@ FROM dunglas/frankenphp
 #     && rm -rf /var/lib/apt/lists/*
 
 # Configure PHP extensions
-RUN install-php-extensions gd opcache
+RUN install-php-extensions gd opcache pdo pdo_sqlite
 
 # Set working directory
 WORKDIR /var/www/html
diff --git a/public_html/_incl/db.php b/public_html/_incl/db.php
new file mode 100644
index 0000000..5980588
--- /dev/null
+++ b/public_html/_incl/db.php
@@ -0,0 +1,589 @@
+<?php
+/**
+ * Axia4 Database Layer
+ *
+ * Provides a PDO SQLite connection and a lightweight migration runner.
+ * All application data previously stored as JSON files under /DATA is now
+ * persisted in /DATA/axia4.db.
+ *
+ * Usage:  db()  → returns the shared PDO instance (auto-migrates on first call).
+ */
+
+define('DB_PATH',        '/DATA/axia4.db');
+define('MIGRATIONS_DIR', __DIR__ . '/migrations');
+
+// ── Connection ────────────────────────────────────────────────────────────────
+
+function db(): PDO
+{
+    static $pdo = null;
+    if ($pdo !== null) {
+        return $pdo;
+    }
+
+    if (!is_dir('/DATA')) {
+        mkdir('/DATA', 0755, true);
+    }
+
+    $pdo = new PDO('sqlite:' . DB_PATH);
+    $pdo->setAttribute(PDO::ATTR_ERRMODE,            PDO::ERRMODE_EXCEPTION);
+    $pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
+    $pdo->exec('PRAGMA journal_mode = WAL');
+    $pdo->exec('PRAGMA foreign_keys = ON');
+    $pdo->exec('PRAGMA synchronous   = NORMAL');
+
+    db_migrate($pdo);
+
+    return $pdo;
+}
+
+// ── Migration runner ──────────────────────────────────────────────────────────
+
+function db_migrate(PDO $pdo): void
+{
+    $pdo->exec(
+        'CREATE TABLE IF NOT EXISTS schema_migrations (
+            version    INTEGER PRIMARY KEY,
+            applied_at TEXT NOT NULL DEFAULT (datetime(\'now\'))
+        )'
+    );
+
+    $applied = $pdo->query('SELECT version FROM schema_migrations ORDER BY version')
+                   ->fetchAll(PDO::FETCH_COLUMN);
+
+    $files = glob(MIGRATIONS_DIR . '/*.{sql,php}', GLOB_BRACE) ?: [];
+    sort($files);
+
+    foreach ($files as $file) {
+        if (!preg_match('/^(\d+)/', basename($file), $m)) {
+            continue;
+        }
+        $version = (int) $m[1];
+        if (in_array($version, $applied, true)) {
+            continue;
+        }
+
+        if (str_ends_with($file, '.sql')) {
+            $pdo->exec((string) file_get_contents($file));
+        } elseif (str_ends_with($file, '.php')) {
+            // PHP migration receives the connection as $db
+            $db = $pdo;
+            require $file;
+        }
+
+        $pdo->prepare('INSERT INTO schema_migrations (version) VALUES (?)')->execute([$version]);
+    }
+}
+
+// ── Config helpers ────────────────────────────────────────────────────────────
+
+function db_get_config(string $key, $default = null)
+{
+    $stmt = db()->prepare('SELECT value FROM config WHERE key = ?');
+    $stmt->execute([$key]);
+    $row = $stmt->fetch();
+    if ($row === false) {
+        return $default;
+    }
+    $decoded = json_decode($row['value'], true);
+    return $decoded !== null ? $decoded : $row['value'];
+}
+
+function db_set_config(string $key, $value): void
+{
+    db()->prepare('INSERT OR REPLACE INTO config (key, value) VALUES (?, ?)')
+       ->execute([$key, is_string($value) ? $value : json_encode($value)]);
+}
+
+function db_get_all_config(): array
+{
+    $rows   = db()->query('SELECT key, value FROM config')->fetchAll();
+    $result = [];
+    foreach ($rows as $row) {
+        $decoded = json_decode($row['value'], true);
+        $result[$row['key']] = ($decoded !== null) ? $decoded : $row['value'];
+    }
+    return $result;
+}
+
+// ── User helpers ──────────────────────────────────────────────────────────────
+
+/** Find a user by username (always lower-cased). Returns DB row or null. */
+function db_get_user(string $username): ?array
+{
+    $stmt = db()->prepare('SELECT * FROM users WHERE username = ?');
+    $stmt->execute([strtolower($username)]);
+    $row = $stmt->fetch();
+    return $row !== false ? $row : null;
+}
+
+/** Return all user rows ordered by username. */
+function db_get_all_users(): array
+{
+    return db()->query('SELECT * FROM users ORDER BY username')->fetchAll();
+}
+
+/**
+ * Build the auth_data session array from a DB user row.
+ * Preserves the same format existing code expects:
+ *   auth_data.permissions, auth_data.entreaulas.centro, .role, .aulas, .centros
+ */
+function db_build_auth_data(array $row): array
+{
+    $permissions = json_decode($row['permissions'] ?? '[]', true) ?: [];
+    $meta        = json_decode($row['meta']        ?? '{}', true) ?: [];
+
+    // Fetch all centro assignments for this user
+    $stmt = db()->prepare(
+        'SELECT centro_id, role, aulas
+           FROM user_centros
+          WHERE user_id = ?
+          ORDER BY centro_id'
+    );
+    $stmt->execute([$row['id']]);
+    $centro_rows = $stmt->fetchAll();
+
+    $ea = ['centro' => '', 'centros' => [], 'role' => '', 'aulas' => []];
+    if (!empty($centro_rows)) {
+        $first        = $centro_rows[0];
+        $ea['centro'] = $first['centro_id'];          // legacy compat
+        $ea['role']   = $first['role'];
+        $ea['aulas']  = json_decode($first['aulas'] ?? '[]', true) ?: [];
+        $ea['centros']      = array_column($centro_rows, 'centro_id');
+        $ea['centros_data'] = $centro_rows;
+    }
+
+    return array_merge($meta, [
+        'display_name'  => $row['display_name'],
+        'email'         => $row['email'],
+        'password_hash' => $row['password_hash'],
+        'permissions'   => $permissions,
+        'entreaulas'    => $ea,
+        'google_auth'   => (bool) $row['google_auth'],
+    ]);
+}
+
+/**
+ * Create or update a user.
+ * $data keys: username, display_name, email, password_hash, permissions[],
+ *             google_auth, entreaulas{centro,centros[],role,aulas[]}, + any extra meta.
+ * Returns the user ID.
+ */
+function db_upsert_user(array $data): int
+{
+    $pdo      = db();
+    $username = strtolower((string) ($data['username'] ?? ''));
+
+    $existing = $pdo->prepare('SELECT id FROM users WHERE username = ?');
+    $existing->execute([$username]);
+    $existing_row = $existing->fetch();
+
+    $permissions = json_encode($data['permissions'] ?? []);
+    $meta_skip   = ['username', 'display_name', 'email', 'password_hash',
+                    'permissions', 'entreaulas', 'google_auth'];
+    $meta = [];
+    foreach ($data as $k => $v) {
+        if (!in_array($k, $meta_skip, true)) {
+            $meta[$k] = $v;
+        }
+    }
+
+    if ($existing_row) {
+        $user_id = (int) $existing_row['id'];
+        $upd = $pdo->prepare(
+            "UPDATE users SET
+                display_name  = ?,
+                email         = ?,
+                permissions   = ?,
+                google_auth   = ?,
+                meta          = ?,
+                updated_at    = datetime('now')
+             WHERE id = ?"
+        );
+        $upd->execute([
+            $data['display_name'] ?? '',
+            $data['email']        ?? '',
+            $permissions,
+            (int) ($data['google_auth'] ?? 0),
+            json_encode($meta),
+            $user_id,
+        ]);
+        if (!empty($data['password_hash'])) {
+            $pdo->prepare('UPDATE users SET password_hash = ? WHERE id = ?')
+                ->execute([$data['password_hash'], $user_id]);
+        }
+    } else {
+        $pdo->prepare(
+            'INSERT INTO users (username, display_name, email, password_hash, permissions, google_auth, meta)
+             VALUES (?, ?, ?, ?, ?, ?, ?)'
+        )->execute([
+            $username,
+            $data['display_name'] ?? '',
+            $data['email']        ?? '',
+            $data['password_hash'] ?? '',
+            $permissions,
+            (int) ($data['google_auth'] ?? 0),
+            json_encode($meta),
+        ]);
+        $user_id = (int) $pdo->lastInsertId();
+    }
+
+    // Update centro assignments when entreaulas data is provided
+    if (array_key_exists('entreaulas', $data)) {
+        $ea = $data['entreaulas'] ?? [];
+        $pdo->prepare('DELETE FROM user_centros WHERE user_id = ?')->execute([$user_id]);
+
+        // Support both legacy single centro and new multi-centro
+        $centros = [];
+        if (!empty($ea['centros']) && is_array($ea['centros'])) {
+            $centros = $ea['centros'];
+        } elseif (!empty($ea['centro'])) {
+            $centros = [$ea['centro']];
+        }
+        $role  = $ea['role']  ?? '';
+        $aulas = json_encode($ea['aulas'] ?? []);
+
+        $ins_centro = $pdo->prepare('INSERT OR IGNORE INTO centros (centro_id) VALUES (?)');
+        $ins_uc = $pdo->prepare(
+            'INSERT OR REPLACE INTO user_centros (user_id, centro_id, role, aulas) VALUES (?, ?, ?, ?)'
+        );
+        foreach ($centros as $cid) {
+            if ($cid === '') {
+                continue;
+            }
+            $ins_centro->execute([$cid]);
+            $ins_uc->execute([$user_id, $cid, $role, $aulas]);
+        }
+    }
+
+    return $user_id;
+}
+
+/** Delete a user and their centro assignments. */
+function db_delete_user(string $username): void
+{
+    db()->prepare('DELETE FROM users WHERE username = ?')->execute([strtolower($username)]);
+}
+
+// ── Centro helpers ────────────────────────────────────────────────────────────
+
+function db_get_centros(): array
+{
+    return db()->query('SELECT centro_id, name FROM centros ORDER BY centro_id')->fetchAll();
+}
+
+function db_get_centro_ids(): array
+{
+    return db()->query('SELECT centro_id FROM centros ORDER BY centro_id')->fetchAll(PDO::FETCH_COLUMN);
+}
+
+// ── Aulario helpers ───────────────────────────────────────────────────────────
+
+/** Get a single aulario config. Returns merged array (name, icon, + extra fields) or null. */
+function db_get_aulario(string $centro_id, string $aulario_id): ?array
+{
+    $stmt = db()->prepare(
+        'SELECT name, icon, extra FROM aularios WHERE centro_id = ? AND aulario_id = ?'
+    );
+    $stmt->execute([$centro_id, $aulario_id]);
+    $row = $stmt->fetch();
+    if ($row === false) {
+        return null;
+    }
+    $extra = json_decode($row['extra'] ?? '{}', true) ?: [];
+    return array_merge($extra, ['name' => $row['name'], 'icon' => $row['icon']]);
+}
+
+/** Get all aularios for a centro as aulario_id → config array. */
+function db_get_aularios(string $centro_id): array
+{
+    $stmt = db()->prepare(
+        'SELECT aulario_id, name, icon, extra FROM aularios WHERE centro_id = ? ORDER BY aulario_id'
+    );
+    $stmt->execute([$centro_id]);
+    $result = [];
+    foreach ($stmt->fetchAll() as $row) {
+        $extra = json_decode($row['extra'] ?? '{}', true) ?: [];
+        $result[$row['aulario_id']] = array_merge($extra, [
+            'name' => $row['name'],
+            'icon' => $row['icon'],
+        ]);
+    }
+    return $result;
+}
+
+// ── SuperCafe helpers ─────────────────────────────────────────────────────────
+
+function db_get_supercafe_menu(string $centro_id): array
+{
+    $stmt = db()->prepare('SELECT data FROM supercafe_menu WHERE centro_id = ?');
+    $stmt->execute([$centro_id]);
+    $row = $stmt->fetch();
+    if ($row === false) {
+        return [];
+    }
+    return json_decode($row['data'], true) ?: [];
+}
+
+function db_set_supercafe_menu(string $centro_id, array $menu): void
+{
+    db()->prepare('INSERT OR REPLACE INTO supercafe_menu (centro_id, data, updated_at) VALUES (?, ?, datetime(\'now\'))')
+       ->execute([$centro_id, json_encode($menu, JSON_UNESCAPED_UNICODE)]);
+}
+
+/** Return all SC orders for a centro as an array of rows. */
+function db_get_supercafe_orders(string $centro_id): array
+{
+    $stmt = db()->prepare(
+        'SELECT * FROM supercafe_orders WHERE centro_id = ? ORDER BY created_at DESC'
+    );
+    $stmt->execute([$centro_id]);
+    return $stmt->fetchAll();
+}
+
+/** Return a single SC order by ref, or null. */
+function db_get_supercafe_order(string $centro_id, string $order_ref): ?array
+{
+    $stmt = db()->prepare(
+        'SELECT * FROM supercafe_orders WHERE centro_id = ? AND order_ref = ?'
+    );
+    $stmt->execute([$centro_id, $order_ref]);
+    $row = $stmt->fetch();
+    return $row !== false ? $row : null;
+}
+
+/** Create or update an SC order. */
+function db_upsert_supercafe_order(
+    string $centro_id,
+    string $order_ref,
+    string $fecha,
+    string $persona,
+    string $comanda,
+    string $notas,
+    string $estado
+): void {
+    db()->prepare(
+        'INSERT INTO supercafe_orders (centro_id, order_ref, fecha, persona, comanda, notas, estado)
+             VALUES (?, ?, ?, ?, ?, ?, ?)
+         ON CONFLICT(centro_id, order_ref) DO UPDATE SET
+             fecha    = excluded.fecha,
+             persona  = excluded.persona,
+             comanda  = excluded.comanda,
+             notas    = excluded.notas,
+             estado   = excluded.estado'
+    )->execute([$centro_id, $order_ref, $fecha, $persona, $comanda, $notas, $estado]);
+}
+
+/** Generate the next order_ref for a centro (sc001, sc002, …). */
+function db_next_supercafe_ref(string $centro_id): string
+{
+    $stmt = db()->prepare(
+        "SELECT order_ref FROM supercafe_orders WHERE centro_id = ? ORDER BY id DESC LIMIT 1"
+    );
+    $stmt->execute([$centro_id]);
+    $last = $stmt->fetchColumn();
+    $n = 0;
+    if ($last && preg_match('/^sc(\d+)$/', $last, $m)) {
+        $n = (int) $m[1];
+    }
+    return 'sc' . str_pad($n + 1, 3, '0', STR_PAD_LEFT);
+}
+
+/** Count 'Deuda' orders for a persona in a centro. */
+function db_supercafe_count_debts(string $centro_id, string $persona_key): int
+{
+    $stmt = db()->prepare(
+        "SELECT COUNT(*) FROM supercafe_orders WHERE centro_id = ? AND persona = ? AND estado = 'Deuda'"
+    );
+    $stmt->execute([$centro_id, $persona_key]);
+    return (int) $stmt->fetchColumn();
+}
+
+// ── Comedor helpers ───────────────────────────────────────────────────────────
+
+function db_get_comedor_menu_types(string $centro_id, string $aulario_id): array
+{
+    $stmt = db()->prepare(
+        'SELECT data FROM comedor_menu_types WHERE centro_id = ? AND aulario_id = ?'
+    );
+    $stmt->execute([$centro_id, $aulario_id]);
+    $row = $stmt->fetch();
+    if ($row === false) {
+        return [];
+    }
+    return json_decode($row['data'], true) ?: [];
+}
+
+function db_set_comedor_menu_types(string $centro_id, string $aulario_id, array $types): void
+{
+    db()->prepare(
+        'INSERT OR REPLACE INTO comedor_menu_types (centro_id, aulario_id, data) VALUES (?, ?, ?)'
+    )->execute([$centro_id, $aulario_id, json_encode($types, JSON_UNESCAPED_UNICODE)]);
+}
+
+function db_get_comedor_entry(string $centro_id, string $aulario_id, string $ym, string $day): array
+{
+    $stmt = db()->prepare(
+        'SELECT data FROM comedor_entries WHERE centro_id = ? AND aulario_id = ? AND year_month = ? AND day = ?'
+    );
+    $stmt->execute([$centro_id, $aulario_id, $ym, $day]);
+    $row = $stmt->fetch();
+    if ($row === false) {
+        return [];
+    }
+    return json_decode($row['data'], true) ?: [];
+}
+
+function db_set_comedor_entry(string $centro_id, string $aulario_id, string $ym, string $day, array $data): void
+{
+    db()->prepare(
+        'INSERT OR REPLACE INTO comedor_entries (centro_id, aulario_id, year_month, day, data) VALUES (?, ?, ?, ?, ?)'
+    )->execute([$centro_id, $aulario_id, $ym, $day, json_encode($data, JSON_UNESCAPED_UNICODE)]);
+}
+
+// ── Diario helpers ────────────────────────────────────────────────────────────
+
+function db_get_diario_entry(string $centro_id, string $aulario_id, string $entry_date): array
+{
+    $stmt = db()->prepare(
+        'SELECT data FROM diario_entries WHERE centro_id = ? AND aulario_id = ? AND entry_date = ?'
+    );
+    $stmt->execute([$centro_id, $aulario_id, $entry_date]);
+    $row = $stmt->fetch();
+    if ($row === false) {
+        return [];
+    }
+    return json_decode($row['data'], true) ?: [];
+}
+
+function db_set_diario_entry(string $centro_id, string $aulario_id, string $entry_date, array $data): void
+{
+    db()->prepare(
+        'INSERT OR REPLACE INTO diario_entries (centro_id, aulario_id, entry_date, data) VALUES (?, ?, ?, ?)'
+    )->execute([$centro_id, $aulario_id, $entry_date, json_encode($data, JSON_UNESCAPED_UNICODE)]);
+}
+
+// ── Panel alumno helpers ──────────────────────────────────────────────────────
+
+function db_get_panel_alumno(string $centro_id, string $aulario_id, string $alumno): array
+{
+    $stmt = db()->prepare(
+        'SELECT data FROM panel_alumno WHERE centro_id = ? AND aulario_id = ? AND alumno = ?'
+    );
+    $stmt->execute([$centro_id, $aulario_id, $alumno]);
+    $row = $stmt->fetch();
+    if ($row === false) {
+        return [];
+    }
+    return json_decode($row['data'], true) ?: [];
+}
+
+function db_set_panel_alumno(string $centro_id, string $aulario_id, string $alumno, array $data): void
+{
+    db()->prepare(
+        'INSERT OR REPLACE INTO panel_alumno (centro_id, aulario_id, alumno, data) VALUES (?, ?, ?, ?)'
+    )->execute([$centro_id, $aulario_id, $alumno, json_encode($data, JSON_UNESCAPED_UNICODE)]);
+}
+
+// ── Invitation helpers ────────────────────────────────────────────────────────
+
+function db_get_all_invitations(): array
+{
+    return db()->query('SELECT * FROM invitations ORDER BY code')->fetchAll();
+}
+
+function db_get_invitation(string $code): ?array
+{
+    $stmt = db()->prepare('SELECT * FROM invitations WHERE code = ?');
+    $stmt->execute([strtoupper($code)]);
+    $row = $stmt->fetch();
+    return $row !== false ? $row : null;
+}
+
+function db_upsert_invitation(string $code, bool $active, bool $single_use): void
+{
+    db()->prepare(
+        'INSERT OR REPLACE INTO invitations (code, active, single_use) VALUES (?, ?, ?)'
+    )->execute([strtoupper($code), (int) $active, (int) $single_use]);
+}
+
+function db_deactivate_invitation(string $code): void
+{
+    db()->prepare('UPDATE invitations SET active = 0 WHERE code = ?')->execute([strtoupper($code)]);
+}
+
+function db_delete_invitation(string $code): void
+{
+    db()->prepare('DELETE FROM invitations WHERE code = ?')->execute([strtoupper($code)]);
+}
+
+// ── Club helpers ──────────────────────────────────────────────────────────────
+
+function db_get_club_config(): array
+{
+    $stmt = db()->query('SELECT data FROM club_config WHERE id = 1');
+    $row  = $stmt->fetch();
+    if ($row === false) {
+        return [];
+    }
+    return json_decode($row['data'], true) ?: [];
+}
+
+function db_set_club_config(array $config): void
+{
+    db()->prepare('INSERT OR REPLACE INTO club_config (id, data) VALUES (1, ?)')
+       ->execute([json_encode($config, JSON_UNESCAPED_UNICODE)]);
+}
+
+function db_get_all_club_events(): array
+{
+    return db()->query('SELECT date_ref, data FROM club_events ORDER BY date_ref DESC')->fetchAll();
+}
+
+function db_get_club_event(string $date_ref): array
+{
+    $stmt = db()->prepare('SELECT data FROM club_events WHERE date_ref = ?');
+    $stmt->execute([$date_ref]);
+    $row = $stmt->fetch();
+    if ($row === false) {
+        return [];
+    }
+    return json_decode($row['data'], true) ?: [];
+}
+
+function db_set_club_event(string $date_ref, array $data): void
+{
+    db()->prepare('INSERT OR REPLACE INTO club_events (date_ref, data) VALUES (?, ?)')
+       ->execute([$date_ref, json_encode($data, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES)]);
+}
+
+// ── Multi-tenant helpers ──────────────────────────────────────────────────────
+
+/** Return all centro IDs the authenticated user belongs to. */
+function get_user_centros(?array $auth_data = null): array
+{
+    $data = $auth_data ?? $_SESSION['auth_data'] ?? [];
+    $ea   = $data['entreaulas'] ?? [];
+
+    if (!empty($ea['centros']) && is_array($ea['centros'])) {
+        return array_values($ea['centros']);
+    }
+    if (!empty($ea['centro'])) {
+        return [$ea['centro']];
+    }
+    return [];
+}
+
+/** Ensure $_SESSION['active_centro'] is set to a valid centro. */
+function init_active_centro(?array $auth_data = null): void
+{
+    $centros = get_user_centros($auth_data);
+    if (empty($centros)) {
+        $_SESSION['active_centro'] = null;
+        return;
+    }
+    if (!empty($_SESSION['active_centro']) && in_array($_SESSION['active_centro'], $centros, true)) {
+        return;
+    }
+    $_SESSION['active_centro'] = $centros[0];
+}
diff --git a/public_html/_incl/migrations/001_initial_schema.sql b/public_html/_incl/migrations/001_initial_schema.sql
new file mode 100644
index 0000000..a73a859
--- /dev/null
+++ b/public_html/_incl/migrations/001_initial_schema.sql
@@ -0,0 +1,144 @@
+-- Axia4 Migration 001: Initial Schema
+-- Converts all JSON file-based storage to a proper relational schema.
+
+PRAGMA journal_mode = WAL;
+PRAGMA foreign_keys = ON;
+
+-- ── Application configuration (replaces /DATA/AuthConfig.json) ─────────────
+CREATE TABLE IF NOT EXISTS config (
+    key        TEXT PRIMARY KEY,
+    value      TEXT NOT NULL DEFAULT ''
+);
+
+-- ── System installation flag (replaces /DATA/SISTEMA_INSTALADO.txt) ────────
+-- Stored as a config row: key='installed', value='1'
+
+-- ── Users (replaces /DATA/Usuarios/*.json) ─────────────────────────────────
+CREATE TABLE IF NOT EXISTS users (
+    id            INTEGER PRIMARY KEY AUTOINCREMENT,
+    username      TEXT    UNIQUE NOT NULL,
+    display_name  TEXT    NOT NULL DEFAULT '',
+    email         TEXT    NOT NULL DEFAULT '',
+    password_hash TEXT    NOT NULL DEFAULT '',
+    permissions   TEXT    NOT NULL DEFAULT '[]',  -- JSON array
+    google_auth   INTEGER NOT NULL DEFAULT 0,
+    meta          TEXT    NOT NULL DEFAULT '{}',   -- JSON for extra fields
+    created_at    TEXT    NOT NULL DEFAULT (datetime('now')),
+    updated_at    TEXT    NOT NULL DEFAULT (datetime('now'))
+);
+
+-- ── Invitations (replaces /DATA/Invitaciones_de_usuarios.json) ─────────────
+CREATE TABLE IF NOT EXISTS invitations (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    code       TEXT    UNIQUE NOT NULL,
+    active     INTEGER NOT NULL DEFAULT 1,
+    single_use INTEGER NOT NULL DEFAULT 1,
+    created_at TEXT    NOT NULL DEFAULT (datetime('now'))
+);
+
+-- ── Centros/Organizations ───────────────────────────────────────────────────
+-- Replaces directory existence at /DATA/entreaulas/Centros/{centro_id}/
+CREATE TABLE IF NOT EXISTS centros (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    centro_id  TEXT    UNIQUE NOT NULL,
+    name       TEXT    NOT NULL DEFAULT '',
+    created_at TEXT    NOT NULL DEFAULT (datetime('now'))
+);
+
+-- ── User ↔ Centro assignments (many-to-many) ───────────────────────────────
+-- Replaces entreaulas.centro + entreaulas.aulas fields in user JSON.
+-- A single user can belong to multiple centros (multi-tenant).
+CREATE TABLE IF NOT EXISTS user_centros (
+    user_id   INTEGER NOT NULL REFERENCES users(id)           ON DELETE CASCADE,
+    centro_id TEXT    NOT NULL REFERENCES centros(centro_id)  ON DELETE CASCADE,
+    role      TEXT    NOT NULL DEFAULT '',
+    aulas     TEXT    NOT NULL DEFAULT '[]',   -- JSON array of aulario_ids
+    PRIMARY KEY (user_id, centro_id)
+);
+
+-- ── Aularios (replaces /DATA/entreaulas/Centros/{}/Aularios/{id}.json) ──────
+CREATE TABLE IF NOT EXISTS aularios (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    centro_id  TEXT    NOT NULL REFERENCES centros(centro_id) ON DELETE CASCADE,
+    aulario_id TEXT    NOT NULL,
+    name       TEXT    NOT NULL DEFAULT '',
+    icon       TEXT    NOT NULL DEFAULT '',
+    extra      TEXT    NOT NULL DEFAULT '{}',  -- JSON for extra config
+    UNIQUE (centro_id, aulario_id)
+);
+
+-- ── SuperCafe menu (replaces .../SuperCafe/Menu.json) ──────────────────────
+CREATE TABLE IF NOT EXISTS supercafe_menu (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    centro_id  TEXT    NOT NULL REFERENCES centros(centro_id) ON DELETE CASCADE,
+    data       TEXT    NOT NULL DEFAULT '{}',  -- JSON matching existing format
+    updated_at TEXT    NOT NULL DEFAULT (datetime('now')),
+    UNIQUE (centro_id)
+);
+
+-- ── SuperCafe orders (replaces .../SuperCafe/Comandas/*.json) ───────────────
+CREATE TABLE IF NOT EXISTS supercafe_orders (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    centro_id  TEXT    NOT NULL REFERENCES centros(centro_id) ON DELETE CASCADE,
+    order_ref  TEXT    NOT NULL,
+    fecha      TEXT    NOT NULL,
+    persona    TEXT    NOT NULL,
+    comanda    TEXT    NOT NULL DEFAULT '',
+    notas      TEXT    NOT NULL DEFAULT '',
+    estado     TEXT    NOT NULL DEFAULT 'Pedido',
+    created_at TEXT    NOT NULL DEFAULT (datetime('now')),
+    UNIQUE (centro_id, order_ref)
+);
+
+-- ── Comedor menu types (replaces .../Comedor-MenuTypes.json) ────────────────
+CREATE TABLE IF NOT EXISTS comedor_menu_types (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    centro_id  TEXT    NOT NULL REFERENCES centros(centro_id) ON DELETE CASCADE,
+    aulario_id TEXT    NOT NULL,
+    data       TEXT    NOT NULL DEFAULT '[]',  -- JSON array of menu type objs
+    UNIQUE (centro_id, aulario_id)
+);
+
+-- ── Comedor daily entries (replaces .../Comedor/{ym}/{day}/_datos.json) ─────
+CREATE TABLE IF NOT EXISTS comedor_entries (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    centro_id  TEXT    NOT NULL REFERENCES centros(centro_id) ON DELETE CASCADE,
+    aulario_id TEXT    NOT NULL,
+    year_month TEXT    NOT NULL,   -- "2024-01"
+    day        TEXT    NOT NULL,   -- "15"
+    data       TEXT    NOT NULL DEFAULT '{}',
+    UNIQUE (centro_id, aulario_id, year_month, day)
+);
+
+-- ── Diary entries (replaces .../Diario/*.json) ──────────────────────────────
+CREATE TABLE IF NOT EXISTS diario_entries (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    centro_id  TEXT    NOT NULL REFERENCES centros(centro_id) ON DELETE CASCADE,
+    aulario_id TEXT    NOT NULL,
+    entry_date TEXT    NOT NULL,
+    data       TEXT    NOT NULL DEFAULT '{}',
+    UNIQUE (centro_id, aulario_id, entry_date)
+);
+
+-- ── Panel diario per-student data (replaces .../Alumnos/*/Panel.json) ───────
+CREATE TABLE IF NOT EXISTS panel_alumno (
+    id         INTEGER PRIMARY KEY AUTOINCREMENT,
+    centro_id  TEXT    NOT NULL REFERENCES centros(centro_id) ON DELETE CASCADE,
+    aulario_id TEXT    NOT NULL,
+    alumno     TEXT    NOT NULL,
+    data       TEXT    NOT NULL DEFAULT '{}',
+    UNIQUE (centro_id, aulario_id, alumno)
+);
+
+-- ── Club event metadata (replaces /DATA/club/IMG/{date}/data.json) ──────────
+CREATE TABLE IF NOT EXISTS club_events (
+    id       INTEGER PRIMARY KEY AUTOINCREMENT,
+    date_ref TEXT    UNIQUE NOT NULL,
+    data     TEXT    NOT NULL DEFAULT '{}'
+);
+
+-- ── Club configuration (replaces /DATA/club/config.json) ────────────────────
+CREATE TABLE IF NOT EXISTS club_config (
+    id   INTEGER PRIMARY KEY CHECK (id = 1),
+    data TEXT    NOT NULL DEFAULT '{}'
+);
diff --git a/public_html/_incl/migrations/002_import_json.php b/public_html/_incl/migrations/002_import_json.php
new file mode 100644
index 0000000..cbc5e9c
--- /dev/null
+++ b/public_html/_incl/migrations/002_import_json.php
@@ -0,0 +1,255 @@
+<?php
+/**
+ * Migration 002: Import existing JSON data from the filesystem into the DB.
+ * This runs once on first boot after the schema is created.
+ * It is safe to run even if /DATA doesn't have all files – missing files are skipped.
+ *
+ * $db (PDO) is provided by the migration runner in db.php.
+ */
+
+// ── AuthConfig → config table ────────────────────────────────────────────────
+$auth_config_file = '/DATA/AuthConfig.json';
+if (file_exists($auth_config_file)) {
+    $auth_config = json_decode(file_get_contents($auth_config_file), true) ?? [];
+    $ins = $db->prepare("INSERT OR IGNORE INTO config (key, value) VALUES (?, ?)");
+    foreach ($auth_config as $k => $v) {
+        $ins->execute([$k, is_string($v) ? $v : json_encode($v)]);
+    }
+}
+
+// ── SISTEMA_INSTALADO marker ─────────────────────────────────────────────────
+if (file_exists('/DATA/SISTEMA_INSTALADO.txt')) {
+    $db->prepare("INSERT OR IGNORE INTO config (key, value) VALUES ('installed', '1')")->execute();
+}
+
+// ── Users (/DATA/Usuarios/*.json) ────────────────────────────────────────────
+$users_dir = '/DATA/Usuarios';
+if (is_dir($users_dir)) {
+    $ins_user = $db->prepare(
+        "INSERT OR IGNORE INTO users
+             (username, display_name, email, password_hash, permissions, google_auth, meta)
+         VALUES (?, ?, ?, ?, ?, ?, ?)"
+    );
+    $ins_uc = $db->prepare(
+        "INSERT OR IGNORE INTO user_centros (user_id, centro_id, role, aulas)
+         VALUES (?, ?, ?, ?)"
+    );
+    $ins_centro = $db->prepare("INSERT OR IGNORE INTO centros (centro_id) VALUES (?)");
+
+    foreach (glob("$users_dir/*.json") ?: [] as $user_file) {
+        $username = basename($user_file, '.json');
+        $data = json_decode(file_get_contents($user_file), true);
+        if (!is_array($data)) {
+            continue;
+        }
+        $permissions = isset($data['permissions']) ? json_encode($data['permissions']) : '[]';
+        // Store remaining non-standard keys in meta
+        $meta_keys = ['display_name', 'email', 'password_hash', 'permissions', 'entreaulas', 'google_auth'];
+        $meta = [];
+        foreach ($data as $k => $v) {
+            if (!in_array($k, $meta_keys, true)) {
+                $meta[$k] = $v;
+            }
+        }
+        $ins_user->execute([
+            $username,
+            $data['display_name'] ?? '',
+            $data['email'] ?? '',
+            $data['password_hash'] ?? '',
+            $permissions,
+            (int) ($data['google_auth'] ?? 0),
+            json_encode($meta),
+        ]);
+        $user_id = (int) $db->lastInsertId();
+        if ($user_id === 0) {
+            // Already existed – look it up
+            $row = $db->prepare("SELECT id FROM users WHERE username = ?")->execute([$username]);
+            $user_id = (int) $db->query("SELECT id FROM users WHERE username = " . $db->quote($username))->fetchColumn();
+        }
+
+        // Entreaulas centro assignment
+        $ea = $data['entreaulas'] ?? [];
+        // Support both old single "centro" and new "centros" array
+        $centros = [];
+        if (!empty($ea['centros']) && is_array($ea['centros'])) {
+            $centros = $ea['centros'];
+        } elseif (!empty($ea['centro'])) {
+            $centros = [$ea['centro']];
+        }
+        $role = $ea['role'] ?? '';
+        $aulas = json_encode($ea['aulas'] ?? []);
+        foreach ($centros as $cid) {
+            if ($cid === '') {
+                continue;
+            }
+            $ins_centro->execute([$cid]);
+            $ins_uc->execute([$user_id, $cid, $role, $aulas]);
+        }
+    }
+}
+
+// ── Invitations (/DATA/Invitaciones_de_usuarios.json) ────────────────────────
+$inv_file = '/DATA/Invitaciones_de_usuarios.json';
+if (file_exists($inv_file)) {
+    $invs = json_decode(file_get_contents($inv_file), true) ?? [];
+    $ins = $db->prepare(
+        "INSERT OR IGNORE INTO invitations (code, active, single_use) VALUES (?, ?, ?)"
+    );
+    foreach ($invs as $code => $inv) {
+        $ins->execute([
+            strtoupper($code),
+            (int) ($inv['active'] ?? 1),
+            (int) ($inv['single_use'] ?? 1),
+        ]);
+    }
+}
+
+// ── Centros & Aularios (directory structure) ──────────────────────────────────
+$centros_base = '/DATA/entreaulas/Centros';
+if (is_dir($centros_base)) {
+    $ins_centro  = $db->prepare("INSERT OR IGNORE INTO centros (centro_id) VALUES (?)");
+    $ins_aulario = $db->prepare(
+        "INSERT OR IGNORE INTO aularios (centro_id, aulario_id, name, icon, extra) VALUES (?, ?, ?, ?, ?)"
+    );
+    foreach (glob("$centros_base/*", GLOB_ONLYDIR) ?: [] as $centro_dir) {
+        $centro_id = basename($centro_dir);
+        $ins_centro->execute([$centro_id]);
+
+        $aularios_dir = "$centro_dir/Aularios";
+        foreach (glob("$aularios_dir/*.json") ?: [] as $aulario_file) {
+            $aulario_id = basename($aulario_file, '.json');
+            $adata = json_decode(file_get_contents($aulario_file), true);
+            if (!is_array($adata)) {
+                continue;
+            }
+            $name  = $adata['name'] ?? $aulario_id;
+            $icon  = $adata['icon'] ?? '';
+            $extra_keys = ['name', 'icon'];
+            $extra = [];
+            foreach ($adata as $k => $v) {
+                if (!in_array($k, $extra_keys, true)) {
+                    $extra[$k] = $v;
+                }
+            }
+            $ins_aulario->execute([$centro_id, $aulario_id, $name, $icon, json_encode($extra)]);
+        }
+
+        // SuperCafe menu
+        $menu_file = "$centro_dir/SuperCafe/Menu.json";
+        if (file_exists($menu_file)) {
+            $menu_data = file_get_contents($menu_file);
+            $db->prepare("INSERT OR IGNORE INTO supercafe_menu (centro_id, data) VALUES (?, ?)")
+               ->execute([$centro_id, $menu_data]);
+        }
+
+        // SuperCafe orders
+        $comandas_dir = "$centro_dir/SuperCafe/Comandas";
+        if (is_dir($comandas_dir)) {
+            $ins_order = $db->prepare(
+                "INSERT OR IGNORE INTO supercafe_orders
+                     (centro_id, order_ref, fecha, persona, comanda, notas, estado)
+                 VALUES (?, ?, ?, ?, ?, ?, ?)"
+            );
+            foreach (glob("$comandas_dir/*.json") ?: [] as $order_file) {
+                $order_ref = basename($order_file, '.json');
+                $odata = json_decode(file_get_contents($order_file), true);
+                if (!is_array($odata)) {
+                    continue;
+                }
+                $ins_order->execute([
+                    $centro_id,
+                    $order_ref,
+                    $odata['Fecha']   ?? '',
+                    $odata['Persona'] ?? '',
+                    $odata['Comanda'] ?? '',
+                    $odata['Notas']   ?? '',
+                    $odata['Estado']  ?? 'Pedido',
+                ]);
+            }
+        }
+
+        // Comedor menu types & daily entries per aulario
+        foreach (glob("$aularios_dir/*.json") ?: [] as $aulario_file) {
+            $aulario_id = basename($aulario_file, '.json');
+
+            $menu_types_file = "$aularios_dir/$aulario_id/Comedor-MenuTypes.json";
+            if (file_exists($menu_types_file)) {
+                $db->prepare(
+                    "INSERT OR IGNORE INTO comedor_menu_types (centro_id, aulario_id, data) VALUES (?, ?, ?)"
+                )->execute([$centro_id, $aulario_id, file_get_contents($menu_types_file)]);
+            }
+
+            $comedor_base = "$aularios_dir/$aulario_id/Comedor";
+            if (is_dir($comedor_base)) {
+                $ins_centry = $db->prepare(
+                    "INSERT OR IGNORE INTO comedor_entries (centro_id, aulario_id, year_month, day, data) VALUES (?, ?, ?, ?, ?)"
+                );
+                foreach (glob("$comedor_base/*", GLOB_ONLYDIR) ?: [] as $ym_dir) {
+                    $ym = basename($ym_dir);
+                    foreach (glob("$ym_dir/*", GLOB_ONLYDIR) ?: [] as $day_dir) {
+                        $day = basename($day_dir);
+                        $data_file = "$day_dir/_datos.json";
+                        if (file_exists($data_file)) {
+                            $ins_centry->execute([
+                                $centro_id, $aulario_id, $ym, $day,
+                                file_get_contents($data_file),
+                            ]);
+                        }
+                    }
+                }
+            }
+
+            // Diario entries
+            $diario_base = "$aularios_dir/$aulario_id/Diario";
+            if (is_dir($diario_base)) {
+                $ins_d = $db->prepare(
+                    "INSERT OR IGNORE INTO diario_entries (centro_id, aulario_id, entry_date, data) VALUES (?, ?, ?, ?)"
+                );
+                foreach (glob("$diario_base/*.json") ?: [] as $diario_file) {
+                    $entry_date = basename($diario_file, '.json');
+                    $ins_d->execute([$centro_id, $aulario_id, $entry_date, file_get_contents($diario_file)]);
+                }
+            }
+
+            // Panel alumno data
+            $alumnos_base = "$aularios_dir/$aulario_id/Alumnos";
+            if (is_dir($alumnos_base)) {
+                $ins_pa = $db->prepare(
+                    "INSERT OR IGNORE INTO panel_alumno (centro_id, aulario_id, alumno, data) VALUES (?, ?, ?, ?)"
+                );
+                foreach (glob("$alumnos_base/*/", GLOB_ONLYDIR) ?: [] as $alumno_dir) {
+                    $alumno = basename($alumno_dir);
+                    // Look for Panel.json (used by paneldiario)
+                    $panel_files = glob("$alumno_dir/Panel*.json") ?: [];
+                    foreach ($panel_files as $pf) {
+                        $ins_pa->execute([
+                            $centro_id, $aulario_id, $alumno,
+                            file_get_contents($pf),
+                        ]);
+                    }
+                }
+            }
+        }
+    }
+}
+
+// ── Club config (/DATA/club/config.json) ──────────────────────────────────────
+$club_config_file = '/DATA/club/config.json';
+if (file_exists($club_config_file)) {
+    $db->prepare("INSERT OR IGNORE INTO club_config (id, data) VALUES (1, ?)")
+       ->execute([file_get_contents($club_config_file)]);
+}
+
+// ── Club events (/DATA/club/IMG/{date}/data.json) ─────────────────────────────
+$club_img_dir = '/DATA/club/IMG';
+if (is_dir($club_img_dir)) {
+    $ins_ev = $db->prepare("INSERT OR IGNORE INTO club_events (date_ref, data) VALUES (?, ?)");
+    foreach (glob("$club_img_dir/*/", GLOB_ONLYDIR) ?: [] as $event_dir) {
+        $date_ref = basename($event_dir);
+        $event_data_file = "$event_dir/data.json";
+        $ins_ev->execute([
+            $date_ref,
+            file_exists($event_data_file) ? file_get_contents($event_data_file) : '{}',
+        ]);
+    }
+}
diff --git a/public_html/_incl/pre-body.php b/public_html/_incl/pre-body.php
index 9a39d47..0c4cc49 100755
--- a/public_html/_incl/pre-body.php
+++ b/public_html/_incl/pre-body.php
@@ -27,7 +27,11 @@ if (!empty($displayName)) {
   $initials = mb_strtoupper($first . $last);
 }
 
-?>
+// Tenant (centro) management
+$userCentros  = get_user_centros($_SESSION["auth_data"] ?? []);
+$activeCentro = $_SESSION['active_centro'] ?? ($_SESSION["auth_data"]["entreaulas"]["centro"] ?? '');
+
+
 <!DOCTYPE html>
 <html lang="es">
 
@@ -526,6 +530,28 @@ if (!empty($displayName)) {
                   <div class="account-name"><?php echo htmlspecialchars($displayName); ?></div>
                   <div class="account-email"><?php echo htmlspecialchars($email); ?></div>
                 </div>
+                <?php if (!empty($userCentros) && $_SESSION["auth_ok"]): ?>
+                <div style="padding: 8px 16px; border-top: 1px solid #e0e0e0;">
+                  <div style="font-size:.75rem;font-weight:600;color:#5f6368;text-transform:uppercase;letter-spacing:.05em;margin-bottom:6px;">
+                    Organización activa
+                  </div>
+                  <div style="font-size:.9rem;font-weight:600;color:#1a73e8;margin-bottom:<?= count($userCentros) > 1 ? '8px' : '0' ?>;">
+                    <?= htmlspecialchars($activeCentro ?: '–') ?>
+                  </div>
+                  <?php if (count($userCentros) > 1): ?>
+                    <div style="font-size:.75rem;color:#5f6368;margin-bottom:4px;">Cambiar organización:</div>
+                    <?php foreach ($userCentros as $cid): if ($cid === $activeCentro) continue; ?>
+                      <form method="post" action="/_incl/switch_tenant.php" style="margin:0 0 4px;">
+                        <input type="hidden" name="redir" value="<?= htmlspecialchars($_SERVER['REQUEST_URI'] ?? '/') ?>">
+                        <button type="submit" name="centro" value="<?= htmlspecialchars($cid) ?>"
+                                style="display:block;width:100%;text-align:left;padding:5px 8px;border:1px solid #e0e0e0;border-radius:6px;background:#f8f9fa;font-size:.85rem;cursor:pointer;">
+                          <?= htmlspecialchars($cid) ?>
+                        </button>
+                      </form>
+                    <?php endforeach; ?>
+                  <?php endif; ?>
+                </div>
+                <?php endif; ?>
                 <div class="account-actions">
                   <?php if ($_SESSION["auth_ok"]) { ?>
                     <a href="/account/" class="btn btn-outline-secondary w-100">Gestionar cuenta</a>
diff --git a/public_html/_incl/switch_tenant.php b/public_html/_incl/switch_tenant.php
new file mode 100644
index 0000000..65e6891
--- /dev/null
+++ b/public_html/_incl/switch_tenant.php
@@ -0,0 +1,28 @@
+<?php
+/**
+ * switch_tenant.php
+ * POST endpoint to switch the active tenant/centro for the current user session.
+ * Validates the requested centro against the user's allowed centros before applying.
+ */
+require_once "tools.session.php";
+require_once "tools.security.php";
+require_once "db.php";
+
+if (!isset($_SESSION["auth_ok"]) || $_SESSION["auth_ok"] !== true) {
+    header("HTTP/1.1 401 Unauthorized");
+    die("No autenticado.");
+}
+
+$requested = Sf($_POST['centro'] ?? '');
+$redir     = safe_redir($_POST['redir'] ?? '/');
+
+$centros = get_user_centros($_SESSION['auth_data'] ?? []);
+
+if ($requested !== '' && in_array($requested, $centros, true)) {
+    $_SESSION['active_centro'] = $requested;
+    // Also update session auth_data so it reflects immediately
+    $_SESSION['auth_data']['entreaulas']['centro'] = $requested;
+}
+
+header("Location: $redir");
+exit;
diff --git a/public_html/_incl/tools.auth.php b/public_html/_incl/tools.auth.php
index d82c66f..6d9a9c0 100644
--- a/public_html/_incl/tools.auth.php
+++ b/public_html/_incl/tools.auth.php
@@ -1,124 +1,80 @@
 <?php
 require_once "tools.session.php";
 require_once "tools.security.php";
+require_once __DIR__ . "/db.php";
+
+// Load auth config from DB (replaces /DATA/AuthConfig.json)
 if (!isset($AuthConfig)) {
-    $AuthConfig = json_decode(file_get_contents("/DATA/AuthConfig.json"), true);
+    $AuthConfig = db_get_all_config();
 }
-$ua = $_SERVER['HTTP_USER_AGENT'];
+
+// ── Header-based auth (Axia4Auth/{user}/{pass}) ───────────────────────────────
+$ua = $_SERVER['HTTP_USER_AGENT'] ?? '';
 if (str_starts_with($ua, "Axia4Auth/")) {
-    $username = explode("/", $ua)[1];
-    $userpass = explode("/", $ua)[2];
-    $user_filename = safe_username_to_filename($username);
-    if ($user_filename === "") {
+    $parts    = explode("/", $ua);
+    $username = $parts[1] ?? '';
+    $userpass = $parts[2] ?? '';
+    $row      = db_get_user($username);
+    if (!$row || !password_verify($userpass, $row['password_hash'])) {
         header("HTTP/1.1 403 Forbidden");
         die();
     }
-    $userdata = json_decode(file_get_contents("/DATA/Usuarios/" . $user_filename . ".json"), true);
-    if (!$userdata) {
-        header("HTTP/1.1 403 Forbidden");
-        die();
-    }
-    if (!password_verify($userpass, $userdata["password_hash"])) {
-        header("HTTP/1.1 403 Forbidden");
-        die();
-    }
-    $_SESSION["auth_user"] = $username;
-    $_SESSION["auth_data"] = $userdata;
-    $_SESSION["auth_ok"] = true;
-    $_COOKIE["auth_user"] = $username;
-    $_COOKIE["auth_pass_b64"] = base64_encode($userpass);
-    $_SESSION["auth_external_lock"] = "header"; // Cannot logout because auth is done via header
+    $_SESSION["auth_user"]          = $username;
+    $_SESSION["auth_data"]          = db_build_auth_data($row);
+    $_SESSION["auth_ok"]            = true;
+    $_COOKIE["auth_user"]           = $username;
+    $_COOKIE["auth_pass_b64"]       = base64_encode($userpass);
+    $_SESSION["auth_external_lock"] = "header";
+    init_active_centro($_SESSION["auth_data"]);
 }
 
-// If $_SESSION is empty, check for cookies "auth_user" and "auth_pass_b64"
-if ($_SESSION["auth_ok"] != true && isset($_COOKIE["auth_user"]) && isset($_COOKIE["auth_pass_b64"])) {
+// ── Cookie-based auto-login ───────────────────────────────────────────────────
+if (($_SESSION["auth_ok"] ?? false) != true
+    && isset($_COOKIE["auth_user"], $_COOKIE["auth_pass_b64"])
+) {
     $username = $_COOKIE["auth_user"];
-    $userpass_b64 = $_COOKIE["auth_pass_b64"];
-    $userpass = base64_decode($userpass_b64);
-    $user_filename = safe_username_to_filename($username);
-    if ($user_filename !== "") {
-        $userdata = json_decode(file_get_contents("/DATA/Usuarios/" . $user_filename . ".json"), true);
-        if ($userdata && password_verify($userpass, $userdata["password_hash"])) {
-            $_SESSION["auth_user"] = $username;
-            $_SESSION["auth_data"] = $userdata;
-            $_SESSION["auth_ok"] = true;
-        }
+    $userpass = base64_decode($_COOKIE["auth_pass_b64"]);
+    $row      = db_get_user($username);
+    if ($row && password_verify($userpass, $row['password_hash'])) {
+        $_SESSION["auth_user"] = $username;
+        $_SESSION["auth_data"] = db_build_auth_data($row);
+        $_SESSION["auth_ok"]   = true;
+        init_active_centro($_SESSION["auth_data"]);
     }
 }
 
-// If session is older than 5min, reload user data
-if (isset($_SESSION["auth_ok"]) && $_SESSION["auth_ok"] && isset($_SESSION["auth_user"])) {
-    if (isset($AuthConfig["session_load_mode"]) && $AuthConfig["session_load_mode"] === "force") {
-        $username = $_SESSION["auth_user"];
-        $user_filename = safe_username_to_filename($username);
-        if ($user_filename !== "") {
-            $userdata = json_decode(file_get_contents("/DATA/Usuarios/" . $user_filename . ".json"), true);
-            $_SESSION["auth_data"] = $userdata;
+// ── Periodic session reload from DB ──────────────────────────────────────────
+if (!empty($_SESSION["auth_ok"]) && !empty($_SESSION["auth_user"])) {
+    $load_mode = $AuthConfig["session_load_mode"] ?? '';
+    if ($load_mode === "force") {
+        $row = db_get_user($_SESSION["auth_user"]);
+        if ($row) {
+            $_SESSION["auth_data"] = db_build_auth_data($row);
+            init_active_centro($_SESSION["auth_data"]);
         }
         $_SESSION["last_reload_time"] = time();
-    } elseif (isset($AuthConfig["session_load_mode"]) && $AuthConfig["session_load_mode"] === "never") {
-        // Do nothing, never reload session data
-    } else {
-        if (isset($_SESSION["last_reload_time"])) {
-            $last_reload = $_SESSION["last_reload_time"];
-            if (time() - $last_reload > 300) {
-                $username = $_SESSION["auth_user"];
-                $user_filename = safe_username_to_filename($username);
-                if ($user_filename !== "") {
-                    $userdata = json_decode(file_get_contents("/DATA/Usuarios/" . $user_filename . ".json"), true);
-                    $_SESSION["auth_data"] = $userdata;
-                }
-                $_SESSION["last_reload_time"] = time();
+    } elseif ($load_mode !== "never") {
+        $last = $_SESSION["last_reload_time"] ?? 0;
+        if (time() - $last > 300) {
+            $row = db_get_user($_SESSION["auth_user"]);
+            if ($row) {
+                $_SESSION["auth_data"] = db_build_auth_data($row);
+                init_active_centro($_SESSION["auth_data"]);
             }
-        } else {
+            $_SESSION["last_reload_time"] = time();
+        }
+        if (!isset($_SESSION["last_reload_time"])) {
             $_SESSION["last_reload_time"] = time();
         }
     }
 }
 
-
-function user_is_authenticated()
+function user_is_authenticated(): bool
 {
     return isset($_SESSION["auth_ok"]) && $_SESSION["auth_ok"] === true;
 }
-function user_has_permission($perm)
-{
-    return in_array($perm, $_SESSION["auth_data"]["permissions"] ?? []);
-}
 
-/**
- * Returns all centro/tenant IDs the authenticated user belongs to.
- * Supports both the legacy single-centro format (entreaulas.centro = "string")
- * and the new multi-tenant format (entreaulas.centros = ["a", "b"]).
- */
-function get_user_centros($auth_data = null)
+function user_has_permission(string $perm): bool
 {
-    $data = $auth_data ?? $_SESSION["auth_data"] ?? [];
-    $ea = $data["entreaulas"] ?? [];
-
-    if (!empty($ea["centros"]) && is_array($ea["centros"])) {
-        return array_values($ea["centros"]);
-    }
-    if (!empty($ea["centro"])) {
-        return [$ea["centro"]];
-    }
-    return [];
-}
-
-/**
- * Ensures $_SESSION['active_centro'] is set to a valid centro for the user.
- * Call after user data is loaded/reloaded.
- */
-function init_active_centro($auth_data = null)
-{
-    $centros = get_user_centros($auth_data);
-    if (empty($centros)) {
-        $_SESSION['active_centro'] = null;
-        return;
-    }
-    // Keep existing selection only if it is still valid
-    if (!empty($_SESSION['active_centro']) && in_array($_SESSION['active_centro'], $centros, true)) {
-        return;
-    }
-    $_SESSION['active_centro'] = $centros[0];
+    return in_array($perm, $_SESSION["auth_data"]["permissions"] ?? [], true);
 }
diff --git a/public_html/_install.php b/public_html/_install.php
index 764e6ca..c9eb756 100644
--- a/public_html/_install.php
+++ b/public_html/_install.php
@@ -1,28 +1,25 @@
 <?php
-if (file_exists("/DATA/SISTEMA_INSTALADO.txt")) {
+require_once "_incl/db.php";
+if (db_get_config('installed') === '1') {
     header("Location: /");
     die();
 }
 
 switch ($_GET['form'] ?? '') {
     case 'create_admin':
-        $admin_user = trim(strtolower($_POST['admin_user'] ?? ''));
+        $admin_user     = trim(strtolower($_POST['admin_user'] ?? ''));
         $admin_password = $_POST['admin_password'] ?? '';
         if (empty($admin_user) || empty($admin_password)) {
             die("El nombre de usuario y la contraseña son obligatorios.");
         }
-        $password_hash = password_hash($admin_password, PASSWORD_DEFAULT);
-        $admin_userdata = [
-            'display_name' => 'Administrador',
-            'email' => "$admin_user@nomail.arpa",
-            'permissions' => ['*', 'sysadmin:access', 'entreaulas:access'],
-            'password_hash' => $password_hash
-        ];
-        if (!is_dir("/DATA/Usuarios")) {
-            mkdir("/DATA/Usuarios", 0777, true);
-        }
-        file_put_contents("/DATA/Usuarios/$admin_user.json", json_encode($admin_userdata, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-        file_put_contents("/DATA/SISTEMA_INSTALADO.txt", "Sistema instalado el ".date("Y-m-d H:i:s")."\n");
+        db_upsert_user([
+            'username'      => $admin_user,
+            'display_name'  => 'Administrador',
+            'email'         => "$admin_user@nomail.arpa",
+            'permissions'   => ['*', 'sysadmin:access', 'entreaulas:access'],
+            'password_hash' => password_hash($admin_password, PASSWORD_DEFAULT),
+        ]);
+        db_set_config('installed', '1');
         header("Location: /_login.php");
         exit;
         break;
diff --git a/public_html/_login.php b/public_html/_login.php
index 324ac4e..98d36e3 100755
--- a/public_html/_login.php
+++ b/public_html/_login.php
@@ -1,8 +1,9 @@
 <?php
 require_once "_incl/tools.session.php";
 require_once "_incl/tools.security.php";
+require_once "_incl/db.php";
 if (!isset($AuthConfig)) {
-    $AuthConfig = json_decode(file_get_contents("/DATA/AuthConfig.json"), true);
+    $AuthConfig = db_get_all_config();
 }
 $DOMAIN = $_SERVER["HTTP_X_FORWARDED_HOST"] ?? $_SERVER["HTTP_HOST"];
 
@@ -21,13 +22,13 @@ function safe_redir($url) {
 }
 
 if ($_GET["reload_user"] == "1") {
-    $user_filename = safe_username_to_filename($_SESSION["auth_user"] ?? "");
-    if ($user_filename === "") {
+    $row = db_get_user($_SESSION["auth_user"] ?? "");
+    if (!$row) {
         header("Location: /");
         die();
     }
-    $userdata = json_decode(file_get_contents("/DATA/Usuarios/" . $user_filename . ".json"), true);
-    $_SESSION['auth_data'] = $userdata;
+    $_SESSION['auth_data'] = db_build_auth_data($row);
+    init_active_centro($_SESSION['auth_data']);
     $redir = safe_redir($_GET["redir"] ?? "/");
     header("Location: $redir");
     die();
@@ -83,34 +84,36 @@ if ($_GET["google_callback"] == "1") {
     }
     
     $email = $user_info["email"];
-    $name = $user_info["name"] ?? explode("@", $email)[0];
-    $user_filename = safe_username_to_filename($email);
-    if ($user_filename === "") {
+    $name  = $user_info["name"] ?? explode("@", $email)[0];
+    $username = strtolower($email);
+    if ($username === "") {
         die("Error: Dirección de correo inválida.");
     }
-    $userfile = "/DATA/Usuarios/" . $user_filename . ".json";
-    $password = bin2hex(random_bytes(16)); // Generar una contraseña aleatoria para el usuario, aunque no se usará para iniciar sesión
-    if (file_exists($userfile)) {
-        $userdata = json_decode(file_get_contents($userfile), true);
+    $password  = bin2hex(random_bytes(16));
+    $existing  = db_get_user($username);
+    if ($existing) {
+        $user_row = $existing;
     } else {
-        $userdata = [
-            "display_name" => $name,
-            "email" => $email,
-            "permissions" => ["public"],
-            "password_hash" => password_hash($password, PASSWORD_DEFAULT),
-            "google_auth" => true,
-            "#" => "Este usuario fue creado automáticamente al iniciar sesión con Google por primera vez.",
-        ];
-        file_put_contents($userfile, json_encode($userdata));
+        db_upsert_user([
+            'username'      => $username,
+            'display_name'  => $name,
+            'email'         => $email,
+            'permissions'   => ['public'],
+            'password_hash' => password_hash($password, PASSWORD_DEFAULT),
+            'google_auth'   => true,
+            '#'             => 'Este usuario fue creado automáticamente al iniciar sesión con Google por primera vez.',
+        ]);
+        $user_row = db_get_user($username);
     }
-    
+
     session_regenerate_id(true);
-    $_SESSION['auth_user'] = $email;
-    $_SESSION['auth_data'] = $userdata;
-    $_SESSION['auth_ok'] = true;
+    $_SESSION['auth_user'] = $username;
+    $_SESSION['auth_data'] = db_build_auth_data($user_row);
+    $_SESSION['auth_ok']   = true;
+    init_active_centro($_SESSION['auth_data']);
     $cookie_options = ["expires" => time() + (86400 * 30), "path" => "/", "httponly" => true, "secure" => true, "samesite" => "Lax"];
-    setcookie("auth_user", $email, $cookie_options);
-    setcookie("auth_pass_b64", base64_encode($password), $cookie_options);
+    setcookie("auth_user",      $username,               $cookie_options);
+    setcookie("auth_pass_b64",  base64_encode($password), $cookie_options);
 
     $redir = safe_redir($state["redir"] ?? "/");
 
@@ -161,20 +164,19 @@ if ($_GET["clear_session"] == "1") {
     die();
 }
 if (isset($_POST["user"])) {
-    $valid = "";
-    $user = trim(strtolower($_POST["user"]));
+    $user     = trim(strtolower($_POST["user"]));
     $password = $_POST["password"];
-    $user_filename = safe_username_to_filename($user);
-    $userdata = ($user_filename !== "") ? json_decode(@file_get_contents("/DATA/Usuarios/" . $user_filename . ".json"), true) : null;
-    if (!is_array($userdata) || !isset($userdata["password_hash"])) {
+    $row      = db_get_user($user);
+    if (!$row || !isset($row["password_hash"])) {
         $_GET["_result"] = "El usuario no existe.";
-    } elseif (password_verify($password, $userdata["password_hash"])) {
+    } elseif (password_verify($password, $row["password_hash"])) {
         session_regenerate_id(true);
         $_SESSION['auth_user'] = $user;
-        $_SESSION['auth_data'] = $userdata;
-        $_SESSION['auth_ok'] = true;
+        $_SESSION['auth_data'] = db_build_auth_data($row);
+        $_SESSION['auth_ok']   = true;
+        init_active_centro($_SESSION['auth_data']);
         $cookie_options = ["expires" => time() + (86400 * 30), "path" => "/", "httponly" => true, "secure" => true, "samesite" => "Lax"];
-        setcookie("auth_user", $user, $cookie_options);
+        setcookie("auth_user",     $user,                    $cookie_options);
         setcookie("auth_pass_b64", base64_encode($password), $cookie_options);
         $redir = safe_redir($_GET["redir"] ?? "/");
         header("Location: $redir");
@@ -182,9 +184,8 @@ if (isset($_POST["user"])) {
     } else {
         $_GET["_result"] = "La contraseña no es correcta.";
     }
-
 }
-if (!file_exists("/DATA/SISTEMA_INSTALADO.txt")) {
+if (db_get_config('installed') !== '1') {
     header("Location: /_install.php");
     die();
 }
diff --git a/public_html/account/index.php b/public_html/account/index.php
index 0ea6b70..aa9838b 100644
--- a/public_html/account/index.php
+++ b/public_html/account/index.php
@@ -1,44 +1,131 @@
 <?php
 require_once "_incl/auth_redir.php";
+require_once "../_incl/db.php";
 require_once "_incl/pre-body.php";
-?>
-<div id="grid">
-    <div class="card pad grid-item" style="text-align: center;">
-        <h2>¡Hola, <?php echo htmlspecialchars($_SESSION["auth_data"]["display_name"]); ?>!</h2>
-        <span><b>Tu Email:</b> <?php echo htmlspecialchars($_SESSION["auth_data"]["email"]); ?></span>
-        <span><b>Tu Nombre de Usuario:</b> <?php echo htmlspecialchars($_SESSION["auth_user"]); ?></span>
-    </div>
-    <div class="card pad grid-item" style="text-align: center;">
-        <b>Código QR</b>
-        <img src="https://api.qrserver.com/v1/create-qr-code/?size=150x150&data=<?php echo urlencode($_SESSION["auth_user"]); ?>" alt="QR Code de Nombre de Usuario" style="margin: 0 auto;">
-        <small>Escanea este código para iniciar sesión. Es como tu contraseña, pero más fácil.</small>
-    </div>
-</div>
-<style>
-    .grid-item {
-        margin-bottom: 10px !important;
-        padding: 15px;
-        width: 300px;
-        text-align: center;
-    }
 
-    .grid-item img {
-        margin: 0 auto;
-        height: 150px;
-    }
+$authData   = $_SESSION["auth_data"] ?? [];
+$username   = $_SESSION["auth_user"] ?? '';
+$displayName = $authData["display_name"] ?? 'Invitado';
+$email      = $authData["email"] ?? '';
+$permissions = $authData["permissions"] ?? [];
+
+// Tenant / centro management
+$userCentros   = get_user_centros($authData);
+$activeCentro  = $_SESSION['active_centro'] ?? ($authData['entreaulas']['centro'] ?? '');
+$aularios      = ($activeCentro !== '') ? db_get_aularios($activeCentro) : [];
+$userAulas     = $authData['entreaulas']['aulas'] ?? [];
+$role          = $authData['entreaulas']['role'] ?? '';
+
+// Initials for avatar
+$parts    = preg_split('/\s+/', trim($displayName));
+$initials = mb_strtoupper(mb_substr($parts[0] ?? '', 0, 1) . mb_substr($parts[1] ?? '', 0, 1));
+if ($initials === '') {
+    $initials = '?';
+}
+?>
+<style>
+.account-grid { display: flex; flex-wrap: wrap; gap: 16px; padding: 16px; }
+.account-card { background: #fff; border: 1px solid #e0e0e0; border-radius: 12px; padding: 24px; min-width: 280px; flex: 1 1 280px; }
+.account-card h2 { font-size: 1rem; font-weight: 600; color: var(--gw-text-secondary, #5f6368); text-transform: uppercase; letter-spacing: .05em; margin: 0 0 16px; }
+.avatar-lg { width: 80px; height: 80px; border-radius: 50%; background: var(--gw-blue, #1a73e8); color: #fff; display: flex; align-items: center; justify-content: center; font-size: 2rem; font-weight: 700; margin: 0 auto 12px; }
+.info-row { display: flex; justify-content: space-between; padding: 6px 0; border-bottom: 1px solid #f1f3f4; font-size: .9rem; }
+.info-row:last-child { border-bottom: none; }
+.info-row .label { color: var(--gw-text-secondary, #5f6368); }
+.badge-pill { display: inline-block; padding: 2px 10px; border-radius: 99px; font-size: .78rem; font-weight: 600; margin: 2px; }
+.badge-active { background: #e6f4ea; color: #137333; }
+.badge-perm { background: #e8f0fe; color: #1a73e8; }
+.tenant-btn { display: block; width: 100%; text-align: left; padding: 8px 12px; border: 1px solid #e0e0e0; border-radius: 8px; margin-bottom: 8px; background: #f8f9fa; cursor: pointer; font-size: .9rem; transition: background .15s; }
+.tenant-btn:hover { background: #e8f0fe; }
+.tenant-btn.active-tenant { border-color: var(--gw-blue, #1a73e8); background: #e8f0fe; font-weight: 600; }
 </style>
-<script>
-    var msnry = new Masonry('#grid', {
-        "columnWidth": 300,
-        "itemSelector": ".grid-item",
-        "gutter": 10,
-        "transitionDuration": 0
-    });
-    setTimeout(() => {
-        msnry.layout()
-    }, 250)
-    setInterval(() => {
-        msnry.layout()
-    }, 1000);
-</script>
-<?php require_once "_incl/post-body.php"; ?>
\ No newline at end of file
+
+<div class="account-grid">
+
+  <!-- Profile Card -->
+  <div class="account-card" style="text-align:center;">
+    <h2>Mi Perfil</h2>
+    <div class="avatar-lg"><?= htmlspecialchars($initials) ?></div>
+    <div style="font-size:1.2rem; font-weight:700; margin-bottom:4px;"><?= htmlspecialchars($displayName) ?></div>
+    <div style="color:var(--gw-text-secondary,#5f6368); margin-bottom:16px;"><?= htmlspecialchars($email ?: 'Sin correo') ?></div>
+    <div class="info-row"><span class="label">Usuario</span><span><?= htmlspecialchars($username) ?></span></div>
+    <?php if ($role): ?>
+    <div class="info-row"><span class="label">Rol</span><span><?= htmlspecialchars($role) ?></span></div>
+    <?php endif; ?>
+    <div style="margin-top:16px;">
+      <a href="/account/change_password.php" class="btn btn-secondary btn-sm">Cambiar contraseña</a>
+    </div>
+  </div>
+
+  <!-- QR Card -->
+  <div class="account-card" style="text-align:center;">
+    <h2>Código QR de Acceso</h2>
+    <img src="https://api.qrserver.com/v1/create-qr-code/?size=150x150&data=<?= urlencode($username) ?>"
+         alt="QR Code" style="margin:0 auto 12px; display:block; width:150px; height:150px;">
+    <small style="color:var(--gw-text-secondary,#5f6368);">Escanea este código para iniciar sesión rápidamente.</small>
+  </div>
+
+  <!-- Tenant / Centro Card -->
+  <?php if (!empty($userCentros)): ?>
+  <div class="account-card">
+    <h2>Organizaciones</h2>
+    <?php foreach ($userCentros as $cid): ?>
+      <form method="post" action="/_incl/switch_tenant.php" style="margin:0;">
+        <input type="hidden" name="redir" value="/account/">
+        <button type="submit" name="centro" value="<?= htmlspecialchars($cid) ?>"
+                class="tenant-btn <?= ($activeCentro === $cid) ? 'active-tenant' : '' ?>">
+          <?php if ($activeCentro === $cid): ?>
+            <span style="color:var(--gw-blue,#1a73e8);">✓ </span>
+          <?php endif; ?>
+          <?= htmlspecialchars($cid) ?>
+          <?php if ($activeCentro === $cid): ?>
+            <span class="badge-pill badge-active" style="float:right;">Activo</span>
+          <?php endif; ?>
+        </button>
+      </form>
+    <?php endforeach; ?>
+  </div>
+  <?php endif; ?>
+
+  <!-- Aulas Card -->
+  <?php if (!empty($userAulas)): ?>
+  <div class="account-card">
+    <h2>Mis Aulas (<?= htmlspecialchars($activeCentro) ?>)</h2>
+    <?php foreach ($userAulas as $aula_id): ?>
+      <?php $aula = $aularios[$aula_id] ?? null; ?>
+      <div class="info-row">
+        <?php if ($aula && !empty($aula['icon'])): ?>
+          <img src="<?= htmlspecialchars($aula['icon']) ?>" style="height:20px;vertical-align:middle;margin-right:6px;">
+        <?php endif; ?>
+        <span><?= htmlspecialchars($aula['name'] ?? $aula_id) ?></span>
+        <span class="badge-pill badge-active">Asignada</span>
+      </div>
+    <?php endforeach; ?>
+  </div>
+  <?php endif; ?>
+
+  <!-- Permissions Card -->
+  <?php if (!empty($permissions)): ?>
+  <div class="account-card">
+    <h2>Permisos</h2>
+    <div>
+      <?php foreach ($permissions as $p): ?>
+        <span class="badge-pill badge-perm"><?= htmlspecialchars($p) ?></span>
+      <?php endforeach; ?>
+    </div>
+  </div>
+  <?php endif; ?>
+
+  <!-- Session Info Card -->
+  <div class="account-card">
+    <h2>Sesión Activa</h2>
+    <div class="info-row"><span class="label">ID Sesión</span><span style="font-family:monospace;font-size:.75rem;"><?= htmlspecialchars(substr(session_id(), 0, 12)) ?>…</span></div>
+    <div class="info-row"><span class="label">Org. activa</span><span><?= htmlspecialchars($activeCentro ?: '–') ?></span></div>
+    <div class="info-row"><span class="label">Autenticación</span><span><?= empty($authData['google_auth']) ? 'Contraseña' : 'Google' ?></span></div>
+    <div style="margin-top:16px;">
+      <a href="/_incl/logout.php" class="btn btn-danger btn-sm">Cerrar sesión</a>
+    </div>
+  </div>
+
+</div>
+
+<?php require_once "_incl/post-body.php"; ?>
diff --git a/public_html/account/register.php b/public_html/account/register.php
index 7dbc0f5..1752e34 100644
--- a/public_html/account/register.php
+++ b/public_html/account/register.php
@@ -1,36 +1,27 @@
 <?php
 require_once "_incl/pre-body.php";
 if ($_SERVER["REQUEST_METHOD"] === "POST") {
-    // Handle form submission
-    $invitations = json_decode(file_get_contents("/DATA/Invitaciones_de_usuarios.json"), true);
-    $invi_code = strtoupper($_POST['invitation_code'] ?? '');
-    if (!isset($invitations[$invi_code])) {
+    $invi_code = strtoupper(trim($_POST['invitation_code'] ?? ''));
+    $invitation = db_get_invitation($invi_code);
+    if (!$invitation || !$invitation['active']) {
         header("Location: /?_resultcolor=red&_result=" . urlencode("Código de invitación no válido."));
         exit;
     }
-    $userdata = [
-        'display_name' => $_POST['display_name'],
-        'email' => $_POST['email'],
-        'password_hash' => password_hash($_POST['password'], PASSWORD_DEFAULT),
-        '_meta_signup' => [
-            'invitation_code' => $invi_code
-        ],
-        'permissions' => []
-    ];
-    if ($invitations[$invi_code]["active"] != true) {
-        header("Location: /?_resultcolor=red&_result=" . urlencode("Código de invitación no válido."));
-        exit;
-    }
-    $username = $_POST['username'];
-    if (file_exists("/DATA/Usuarios/$username.json")) {
+    $username = strtolower(trim($_POST['username'] ?? ''));
+    if (db_get_user($username)) {
         header("Location: /?_resultcolor=red&_result=" . urlencode("El nombre de usuario ya existe. Por favor, elige otro."));
         exit;
     }
-    file_put_contents("/DATA/Usuarios/$username.json", json_encode($userdata, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-    // Deactivate invitation code if it's single-use
-    if ($invitations[$invi_code]["single_use"] === true) {
-        $invitations[$invi_code]["active"] = false;
-        file_put_contents("/DATA/Invitaciones_de_usuarios.json", json_encode($invitations, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
+    db_upsert_user([
+        'username'      => $username,
+        'display_name'  => $_POST['display_name'] ?? '',
+        'email'         => $_POST['email'] ?? '',
+        'password_hash' => password_hash($_POST['password'], PASSWORD_DEFAULT),
+        'permissions'   => [],
+        '_meta_signup'  => ['invitation_code' => $invi_code],
+    ]);
+    if ($invitation['single_use']) {
+        db_deactivate_invitation($invi_code);
     }
     header("Location: /?_result=" . urlencode("Cuenta creada correctamente. Ya puedes iniciar sesión."));
     exit;
diff --git a/public_html/aulatek/api/comedor.php b/public_html/aulatek/api/comedor.php
index 320ca98..36aa8d9 100644
--- a/public_html/aulatek/api/comedor.php
+++ b/public_html/aulatek/api/comedor.php
@@ -2,24 +2,7 @@
 header("Content-Type: application/json; charset=utf-8");
 require_once "_incl/auth_redir.php";
 require_once "../_incl/tools.security.php";
-
-function menu_types_path($centro_id, $aulario_id) {
-    $centro = safe_centro_id($centro_id);
-    $aulario = safe_id_segment($aulario_id);
-    if ($centro === '' || $aulario === '') {
-        return null;
-    }
-    return "/DATA/entreaulas/Centros/$centro/Aularios/$aulario/Comedor-MenuTypes.json";
-}
-
-function comedor_day_base_dir($centro_id, $aulario_id, $ym, $day) {
-    $centro = safe_centro_id($centro_id);
-    $aulario = safe_id_segment($aulario_id);
-    if ($centro === '' || $aulario === '') {
-        return null;
-    }
-    return "/DATA/entreaulas/Centros/$centro/Aularios/$aulario/Comedor/$ym/$day";
-}
+require_once "../../_incl/db.php";
 
 // Check permissions
 if (!in_array("entreaulas:docente", $_SESSION["auth_data"]["permissions"] ?? [])) {
@@ -33,64 +16,48 @@ if ($centro_id === "") {
     die(json_encode(["error" => "Centro not found in session", "code" => "INVALID_SESSION"]));
 }
 
-$action = $_GET["action"] ?? ($_POST["action"] ?? "");
+$action     = $_GET["action"] ?? ($_POST["action"] ?? "");
 $aulario_id = safe_id_segment($_GET["aulario"] ?? $_POST["aulario"] ?? "");
 
-// Validate aulario_id
 if ($aulario_id === "") {
     http_response_code(400);
     die(json_encode(["error" => "aulario parameter is required", "code" => "MISSING_PARAM"]));
 }
 
-// Verify that the user has access to this aulario
-$userAulas = $_SESSION["auth_data"]["entreaulas"]["aulas"] ?? [];
-$userAulas = array_values(array_filter(array_map('safe_id_segment', $userAulas)));
+$userAulas = array_values(array_filter(array_map('safe_id_segment', $_SESSION["auth_data"]["entreaulas"]["aulas"] ?? [])));
 if (!in_array($aulario_id, $userAulas, true)) {
     http_response_code(403);
     die(json_encode(["error" => "Access denied to this aulario", "code" => "FORBIDDEN"]));
 }
 
-$aulario_path = safe_aulario_config_path($centro_id, $aulario_id);
-$aulario = ($aulario_path && file_exists($aulario_path)) ? json_decode(file_get_contents($aulario_path), true) : null;
+$aulario = db_get_aulario($centro_id, $aulario_id);
 
-// Handle shared comedor data
 $source_aulario_id = $aulario_id;
 $is_shared = false;
 if ($aulario && !empty($aulario["shared_comedor_from"])) {
     $shared_from = safe_id_segment($aulario["shared_comedor_from"]);
-    $shared_aulario_path = safe_aulario_config_path($centro_id, $shared_from);
-    if ($shared_aulario_path && file_exists($shared_aulario_path)) {
+    if (db_get_aulario($centro_id, $shared_from)) {
         $source_aulario_id = $shared_from;
         $is_shared = true;
     }
 }
 
-// Check edit permissions (must be sysadmin and not shared)
 $canEdit = in_array("sysadmin:access", $_SESSION["auth_data"]["permissions"] ?? []) && !$is_shared;
 
-// Helper functions
-function get_menu_types($centro_id, $source_aulario_id) {
-    $menuTypesPath = menu_types_path($centro_id, $source_aulario_id);
-    $defaultMenuTypes = [
-        ["id" => "basal", "label" => "Menú basal", "color" => "#0d6efd"],
-        ["id" => "vegetariano", "label" => "Menú vegetariano", "color" => "#198754"],
-        ["id" => "alergias", "label" => "Menú alergias", "color" => "#dc3545"],
-    ];
+$defaultMenuTypes = [
+    ["id" => "basal",       "label" => "Menú basal",       "color" => "#0d6efd"],
+    ["id" => "vegetariano", "label" => "Menú vegetariano", "color" => "#198754"],
+    ["id" => "alergias",    "label" => "Menú alergias",    "color" => "#dc3545"],
+];
 
-    if ($menuTypesPath === null) {
+function get_menu_types($centro_id, $source_aulario_id) {
+    global $defaultMenuTypes;
+    $types = db_get_comedor_menu_types($centro_id, $source_aulario_id);
+    if (empty($types)) {
+        db_set_comedor_menu_types($centro_id, $source_aulario_id, $defaultMenuTypes);
         return $defaultMenuTypes;
     }
-    
-    if (!file_exists($menuTypesPath)) {
-        if (!is_dir(dirname($menuTypesPath))) {
-            mkdir(dirname($menuTypesPath), 0777, true);
-        }
-        file_put_contents($menuTypesPath, json_encode($defaultMenuTypes, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-        return $defaultMenuTypes;
-    }
-    
-    $menuTypes = json_decode(@file_get_contents($menuTypesPath), true);
-    return (is_array($menuTypes) && count($menuTypes) > 0) ? $menuTypes : $defaultMenuTypes;
+    return $types;
 }
 
 function blank_menu() {
@@ -98,7 +65,7 @@ function blank_menu() {
         "plates" => [
             "primero" => ["name" => "", "pictogram" => ""],
             "segundo" => ["name" => "", "pictogram" => ""],
-            "postre" => ["name" => "", "pictogram" => ""],
+            "postre"  => ["name" => "", "pictogram" => ""],
         ]
     ];
 }
@@ -113,43 +80,25 @@ switch ($action) {
     case "get_menu_types":
         handle_get_menu_types();
         break;
-    
     case "get_menu":
         handle_get_menu();
         break;
-    
     case "save_menu":
-        if (!$canEdit) {
-            http_response_code(403);
-            die(json_encode(["error" => "Insufficient permissions to edit", "code" => "FORBIDDEN"]));
-        }
+        if (!$canEdit) { http_response_code(403); die(json_encode(["error" => "Insufficient permissions to edit", "code" => "FORBIDDEN"])); }
         handle_save_menu();
         break;
-    
     case "add_menu_type":
-        if (!$canEdit) {
-            http_response_code(403);
-            die(json_encode(["error" => "Insufficient permissions to edit", "code" => "FORBIDDEN"]));
-        }
+        if (!$canEdit) { http_response_code(403); die(json_encode(["error" => "Insufficient permissions to edit", "code" => "FORBIDDEN"])); }
         handle_add_menu_type();
         break;
-    
     case "delete_menu_type":
-        if (!$canEdit) {
-            http_response_code(403);
-            die(json_encode(["error" => "Insufficient permissions to edit", "code" => "FORBIDDEN"]));
-        }
+        if (!$canEdit) { http_response_code(403); die(json_encode(["error" => "Insufficient permissions to edit", "code" => "FORBIDDEN"])); }
         handle_delete_menu_type();
         break;
-    
     case "rename_menu_type":
-        if (!$canEdit) {
-            http_response_code(403);
-            die(json_encode(["error" => "Insufficient permissions to edit", "code" => "FORBIDDEN"]));
-        }
+        if (!$canEdit) { http_response_code(403); die(json_encode(["error" => "Insufficient permissions to edit", "code" => "FORBIDDEN"])); }
         handle_rename_menu_type();
         break;
-    
     default:
         http_response_code(400);
         die(json_encode(["error" => "Invalid action", "code" => "INVALID_ACTION"]));
@@ -157,298 +106,102 @@ switch ($action) {
 
 function handle_get_menu_types() {
     global $centro_id, $source_aulario_id;
-    
-    $menuTypes = get_menu_types($centro_id, $source_aulario_id);
-    echo json_encode([
-        "success" => true,
-        "menu_types" => $menuTypes
-    ]);
+    echo json_encode(["success" => true, "menu_types" => get_menu_types($centro_id, $source_aulario_id)]);
 }
 
 function handle_get_menu() {
     global $centro_id, $source_aulario_id;
-    
     $date = $_GET["date"] ?? date("Y-m-d");
     $menuTypeId = safe_id_segment($_GET["menu"] ?? "");
-    
-    // Validate date
     $dateObj = DateTime::createFromFormat("Y-m-d", $date);
-    if (!$dateObj) {
-        http_response_code(400);
-        die(json_encode(["error" => "Invalid date format", "code" => "INVALID_FORMAT"]));
-    }
+    if (!$dateObj) { http_response_code(400); die(json_encode(["error" => "Invalid date format", "code" => "INVALID_FORMAT"])); }
     $date = $dateObj->format("Y-m-d");
-    
-    // Get menu types
-    $menuTypes = get_menu_types($centro_id, $source_aulario_id);
-    $menuTypeIds = [];
-    foreach ($menuTypes as $t) {
-        if (!empty($t["id"])) {
-            $menuTypeIds[] = $t["id"];
-        }
-    }
-    
-    if ($menuTypeId === "" || !in_array($menuTypeId, $menuTypeIds)) {
-        $menuTypeId = $menuTypeIds[0] ?? "basal";
-    }
-    
-    // Get menu data
-    $ym = $dateObj->format("Y-m");
+    $menuTypes   = get_menu_types($centro_id, $source_aulario_id);
+    $menuTypeIds = array_column($menuTypes, "id");
+    if ($menuTypeId === "" || !in_array($menuTypeId, $menuTypeIds)) { $menuTypeId = $menuTypeIds[0] ?? "basal"; }
+    $ym  = $dateObj->format("Y-m");
     $day = $dateObj->format("d");
-    $baseDir = comedor_day_base_dir($centro_id, $source_aulario_id, $ym, $day);
-    if ($baseDir === null) {
-        http_response_code(400);
-        die(json_encode(["error" => "Invalid path parameters", "code" => "INVALID_PATH"]));
-    }
-    $dataPath = "$baseDir/_datos.json";
-    
-    $menuData = [
-        "date" => $date,
-        "menus" => []
-    ];
-    
-    if (file_exists($dataPath)) {
-        $existing = json_decode(file_get_contents($dataPath), true);
-        if (is_array($existing)) {
-            $menuData = array_merge($menuData, $existing);
-        }
-    }
-    
-    if (!isset($menuData["menus"][$menuTypeId])) {
-        $menuData["menus"][$menuTypeId] = blank_menu();
-    }
-    
-    $menuForType = $menuData["menus"][$menuTypeId];
-    
-    echo json_encode([
-        "success" => true,
-        "date" => $date,
-        "menu_type" => $menuTypeId,
-        "menu_types" => $menuTypes,
-        "menu" => $menuForType
-    ]);
+    $menuData = ["date" => $date, "menus" => []];
+    $existing = db_get_comedor_entry($centro_id, $source_aulario_id, $ym, $day);
+    if (!empty($existing)) { $menuData = array_merge($menuData, $existing); }
+    if (!isset($menuData["menus"][$menuTypeId])) { $menuData["menus"][$menuTypeId] = blank_menu(); }
+    echo json_encode(["success" => true, "date" => $date, "menu_type" => $menuTypeId, "menu_types" => $menuTypes, "menu" => $menuData["menus"][$menuTypeId]]);
 }
 
 function handle_save_menu() {
     global $centro_id, $source_aulario_id;
-    
-    // Parse JSON body
-    $input = json_decode(file_get_contents("php://input"), true);
-    if (!$input) {
-        $input = $_POST;
-    }
-    
-    $date = $input["date"] ?? date("Y-m-d");
+    $input = json_decode(file_get_contents("php://input"), true) ?: $_POST;
+    $date       = $input["date"] ?? date("Y-m-d");
     $menuTypeId = safe_id_segment($input["menu_type"] ?? "");
-    $plates = $input["plates"] ?? [];
-    
-    // Validate date
+    $plates     = $input["plates"] ?? [];
     $dateObj = DateTime::createFromFormat("Y-m-d", $date);
-    if (!$dateObj) {
-        http_response_code(400);
-        die(json_encode(["error" => "Invalid date format", "code" => "INVALID_FORMAT"]));
-    }
+    if (!$dateObj) { http_response_code(400); die(json_encode(["error" => "Invalid date format", "code" => "INVALID_FORMAT"])); }
     $date = $dateObj->format("Y-m-d");
-    
-    // Validate menu type
-    $menuTypes = get_menu_types($centro_id, $source_aulario_id);
-    $validMenuTypeIds = [];
-    foreach ($menuTypes as $t) {
-        if (!empty($t["id"])) {
-            $validMenuTypeIds[] = $t["id"];
-        }
-    }
-    
-    if (!in_array($menuTypeId, $validMenuTypeIds)) {
-        http_response_code(400);
-        die(json_encode(["error" => "Invalid menu type", "code" => "INVALID_MENU_TYPE"]));
-    }
-    
-    // Get existing menu data
-    $ym = $dateObj->format("Y-m");
+    $menuTypes      = get_menu_types($centro_id, $source_aulario_id);
+    $validMenuTypeIds = array_column($menuTypes, "id");
+    if (!in_array($menuTypeId, $validMenuTypeIds)) { http_response_code(400); die(json_encode(["error" => "Invalid menu type", "code" => "INVALID_MENU_TYPE"])); }
+    $ym  = $dateObj->format("Y-m");
     $day = $dateObj->format("d");
-    $baseDir = comedor_day_base_dir($centro_id, $source_aulario_id, $ym, $day);
-    if ($baseDir === null) {
-        http_response_code(400);
-        die(json_encode(["error" => "Invalid path parameters", "code" => "INVALID_PATH"]));
-    }
-    $dataPath = "$baseDir/_datos.json";
-    
-    $menuData = [
-        "date" => $date,
-        "menus" => []
-    ];
-    
-    if (file_exists($dataPath)) {
-        $existing = json_decode(file_get_contents($dataPath), true);
-        if (is_array($existing)) {
-            $menuData = array_merge($menuData, $existing);
+    $menuData = ["date" => $date, "menus" => []];
+    $existing = db_get_comedor_entry($centro_id, $source_aulario_id, $ym, $day);
+    if (!empty($existing)) { $menuData = array_merge($menuData, $existing); }
+    if (!isset($menuData["menus"][$menuTypeId])) { $menuData["menus"][$menuTypeId] = blank_menu(); }
+    foreach (["primero", "segundo", "postre"] as $plateKey) {
+        if (isset($plates[$plateKey]["name"])) {
+            $menuData["menus"][$menuTypeId]["plates"][$plateKey]["name"] = trim($plates[$plateKey]["name"]);
         }
     }
-    
-    if (!isset($menuData["menus"][$menuTypeId])) {
-        $menuData["menus"][$menuTypeId] = blank_menu();
-    }
-    
-    // Update plates
-    $validPlates = ["primero", "segundo", "postre"];
-    foreach ($validPlates as $plateKey) {
-        if (isset($plates[$plateKey])) {
-            if (isset($plates[$plateKey]["name"])) {
-                $menuData["menus"][$menuTypeId]["plates"][$plateKey]["name"] = trim($plates[$plateKey]["name"]);
-            }
-            // Note: pictogram upload not supported via JSON API - use form-data instead
-        }
-    }
-    
-    // Save menu
-    if (!is_dir($baseDir)) {
-        mkdir($baseDir, 0777, true);
-    }
-    file_put_contents($dataPath, json_encode($menuData, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-    
-    echo json_encode([
-        "success" => true,
-        "date" => $date,
-        "menu_type" => $menuTypeId,
-        "menu" => $menuData["menus"][$menuTypeId]
-    ]);
+    db_set_comedor_entry($centro_id, $source_aulario_id, $ym, $day, $menuData);
+    echo json_encode(["success" => true, "date" => $date, "menu_type" => $menuTypeId, "menu" => $menuData["menus"][$menuTypeId]]);
 }
 
 function handle_add_menu_type() {
     global $centro_id, $source_aulario_id;
-    
-    $input = json_decode(file_get_contents("php://input"), true);
-    if (!$input) {
-        $input = $_POST;
-    }
-    
-    $newId = safe_id_segment(strtolower(trim($input["id"] ?? "")));
+    $input    = json_decode(file_get_contents("php://input"), true) ?: $_POST;
+    $newId    = safe_id_segment(strtolower(trim($input["id"] ?? "")));
     $newLabel = trim($input["label"] ?? "");
     $newColor = trim($input["color"] ?? "#0d6efd");
-    
-    if ($newId === "" || $newLabel === "") {
-        http_response_code(400);
-        die(json_encode(["error" => "id and label are required", "code" => "MISSING_PARAM"]));
-    }
-    
-    $menuTypesPath = menu_types_path($centro_id, $source_aulario_id);
-    if ($menuTypesPath === null) {
-        http_response_code(400);
-        die(json_encode(["error" => "Invalid path parameters", "code" => "INVALID_PATH"]));
-    }
+    if ($newId === "" || $newLabel === "") { http_response_code(400); die(json_encode(["error" => "id and label are required", "code" => "MISSING_PARAM"])); }
     $menuTypes = get_menu_types($centro_id, $source_aulario_id);
-    
-    // Check if already exists
     foreach ($menuTypes as $t) {
-        if (($t["id"] ?? "") === $newId) {
-            http_response_code(400);
-            die(json_encode(["error" => "Menu type already exists", "code" => "DUPLICATE"]));
-        }
+        if (($t["id"] ?? "") === $newId) { http_response_code(400); die(json_encode(["error" => "Menu type already exists", "code" => "DUPLICATE"])); }
     }
-    
     $menuTypes[] = ["id" => $newId, "label" => $newLabel, "color" => $newColor];
-    file_put_contents($menuTypesPath, json_encode($menuTypes, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-    
-    echo json_encode([
-        "success" => true,
-        "menu_type" => ["id" => $newId, "label" => $newLabel, "color" => $newColor],
-        "message" => "Menu type added successfully"
-    ]);
+    db_set_comedor_menu_types($centro_id, $source_aulario_id, $menuTypes);
+    echo json_encode(["success" => true, "menu_type" => ["id" => $newId, "label" => $newLabel, "color" => $newColor], "message" => "Menu type added successfully"]);
 }
 
 function handle_delete_menu_type() {
     global $centro_id, $source_aulario_id;
-    
-    $input = json_decode(file_get_contents("php://input"), true);
-    if (!$input) {
-        $input = $_POST;
-    }
-    
+    $input    = json_decode(file_get_contents("php://input"), true) ?: $_POST;
     $deleteId = safe_id_segment(trim($input["id"] ?? ""));
-    
-    if ($deleteId === "") {
-        http_response_code(400);
-        die(json_encode(["error" => "id is required", "code" => "MISSING_PARAM"]));
-    }
-    
-    $menuTypesPath = menu_types_path($centro_id, $source_aulario_id);
-    if ($menuTypesPath === null) {
-        http_response_code(400);
-        die(json_encode(["error" => "Invalid path parameters", "code" => "INVALID_PATH"]));
-    }
-    $menuTypes = get_menu_types($centro_id, $source_aulario_id);
-    
-    $deleted = false;
-    $newMenuTypes = [];
-    foreach ($menuTypes as $t) {
-        if (($t["id"] ?? "") === $deleteId) {
-            $deleted = true;
-        } else {
-            $newMenuTypes[] = $t;
-        }
-    }
-    
-    if (!$deleted) {
-        http_response_code(404);
-        die(json_encode(["error" => "Menu type not found", "code" => "NOT_FOUND"]));
-    }
-    
-    file_put_contents($menuTypesPath, json_encode($newMenuTypes, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-    
-    echo json_encode([
-        "success" => true,
-        "message" => "Menu type deleted successfully"
-    ]);
+    if ($deleteId === "") { http_response_code(400); die(json_encode(["error" => "id is required", "code" => "MISSING_PARAM"])); }
+    $menuTypes    = get_menu_types($centro_id, $source_aulario_id);
+    $newMenuTypes = array_values(array_filter($menuTypes, fn($t) => ($t["id"] ?? "") !== $deleteId));
+    if (count($newMenuTypes) === count($menuTypes)) { http_response_code(404); die(json_encode(["error" => "Menu type not found", "code" => "NOT_FOUND"])); }
+    db_set_comedor_menu_types($centro_id, $source_aulario_id, $newMenuTypes);
+    echo json_encode(["success" => true, "message" => "Menu type deleted successfully"]);
 }
 
 function handle_rename_menu_type() {
     global $centro_id, $source_aulario_id;
-    
-    $input = json_decode(file_get_contents("php://input"), true);
-    if (!$input) {
-        $input = $_POST;
-    }
-    
+    $input    = json_decode(file_get_contents("php://input"), true) ?: $_POST;
     $renameId = safe_id_segment(trim($input["id"] ?? ""));
     $newLabel = trim($input["label"] ?? "");
     $newColor = trim($input["color"] ?? "");
-    
-    if ($renameId === "" || $newLabel === "") {
-        http_response_code(400);
-        die(json_encode(["error" => "id and label are required", "code" => "MISSING_PARAM"]));
-    }
-    
-    $menuTypesPath = menu_types_path($centro_id, $source_aulario_id);
-    if ($menuTypesPath === null) {
-        http_response_code(400);
-        die(json_encode(["error" => "Invalid path parameters", "code" => "INVALID_PATH"]));
-    }
+    if ($renameId === "" || $newLabel === "") { http_response_code(400); die(json_encode(["error" => "id and label are required", "code" => "MISSING_PARAM"])); }
     $menuTypes = get_menu_types($centro_id, $source_aulario_id);
-    
     $found = false;
     foreach ($menuTypes as &$t) {
         if (($t["id"] ?? "") === $renameId) {
             $t["label"] = $newLabel;
-            if ($newColor !== "") {
-                $t["color"] = $newColor;
-            }
+            if ($newColor !== "") { $t["color"] = $newColor; }
             $found = true;
             break;
         }
     }
     unset($t);
-    
-    if (!$found) {
-        http_response_code(404);
-        die(json_encode(["error" => "Menu type not found", "code" => "NOT_FOUND"]));
-    }
-    
-    file_put_contents($menuTypesPath, json_encode($menuTypes, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-    
-    echo json_encode([
-        "success" => true,
-        "menu_type" => ["id" => $renameId, "label" => $newLabel, "color" => $newColor],
-        "message" => "Menu type renamed successfully"
-    ]);
+    if (!$found) { http_response_code(404); die(json_encode(["error" => "Menu type not found", "code" => "NOT_FOUND"])); }
+    db_set_comedor_menu_types($centro_id, $source_aulario_id, $menuTypes);
+    echo json_encode(["success" => true, "message" => "Menu type renamed successfully"]);
 }
diff --git a/public_html/aulatek/aulario.php b/public_html/aulatek/aulario.php
index df80422..9259f3f 100644
--- a/public_html/aulatek/aulario.php
+++ b/public_html/aulatek/aulario.php
@@ -2,11 +2,11 @@
 require_once "_incl/auth_redir.php";
 require_once "_incl/pre-body.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 $aulario_id = safe_id_segment($_GET["id"] ?? "");
-$centro_id = safe_centro_id($_SESSION["auth_data"]["entreaulas"]["centro"] ?? "");
-$aulario_path = safe_aulario_config_path($centro_id, $aulario_id);
-$aulario = ($aulario_path && file_exists($aulario_path)) ? json_decode(file_get_contents($aulario_path), true) : null;
+$centro_id  = safe_centro_id($_SESSION["auth_data"]["entreaulas"]["centro"] ?? "");
+$aulario    = db_get_aulario($centro_id, $aulario_id);
 
 if (!$aulario || !is_array($aulario)) {
 ?>
diff --git a/public_html/aulatek/comedor.php b/public_html/aulatek/comedor.php
index 3b47bdd..32e7d0d 100644
--- a/public_html/aulatek/comedor.php
+++ b/public_html/aulatek/comedor.php
@@ -1,6 +1,7 @@
 <?php
 require_once "_incl/auth_redir.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 if (in_array("entreaulas:docente", $_SESSION["auth_data"]["permissions"] ?? []) === false) {
     header("HTTP/1.1 403 Forbidden");
@@ -22,38 +23,31 @@ if ($aulario_id === "" || $centro_id === "") {
 	exit;
 }
 
-$aulario_path = safe_aulario_config_path($centro_id, $aulario_id);
-$aulario = ($aulario_path && file_exists($aulario_path)) ? json_decode(file_get_contents($aulario_path), true) : null;
+$aulario = db_get_aulario($centro_id, $aulario_id);
 
 // Check if this aulario shares comedor data from another aulario
-$source_aulario_id = $aulario_id; // Default to current aulario
+$source_aulario_id = $aulario_id;
 $is_shared = false;
 if ($aulario && !empty($aulario["shared_comedor_from"])) {
 	$shared_from = safe_id_segment($aulario["shared_comedor_from"]);
-	$shared_aulario_path = safe_aulario_config_path($centro_id, $shared_from);
-	if ($shared_aulario_path && file_exists($shared_aulario_path)) {
-		$source_aulario_id = $shared_from;
-		$source_aulario_name = json_decode(file_get_contents($shared_aulario_path), true)["name"] ?? $shared_from;
+	$shared_aulario = db_get_aulario($centro_id, $shared_from);
+	if ($shared_aulario) {
+		$source_aulario_id   = $shared_from;
+		$source_aulario_name = $shared_aulario["name"] ?? $shared_from;
 		$is_shared = true;
 	}
 }
 
-$menuTypesPath = "/DATA/entreaulas/Centros/$centro_id/Aularios/$source_aulario_id/Comedor-MenuTypes.json";
 $defaultMenuTypes = [
-	["id" => "basal", "label" => "Menú basal", "color" => "#0d6efd"],
+	["id" => "basal",       "label" => "Menú basal",       "color" => "#0d6efd"],
 	["id" => "vegetariano", "label" => "Menú vegetariano", "color" => "#198754"],
-	["id" => "alergias", "label" => "Menú alergias", "color" => "#dc3545"],
+	["id" => "alergias",    "label" => "Menú alergias",    "color" => "#dc3545"],
 ];
-if (!file_exists($menuTypesPath)) {
-	if (!is_dir(dirname($menuTypesPath))) {
-		mkdir(dirname($menuTypesPath), 0777, true);
-	}
-	file_put_contents($menuTypesPath, json_encode($defaultMenuTypes, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-}
 
-$menuTypes = json_decode(@file_get_contents($menuTypesPath), true);
+$menuTypes = db_get_comedor_menu_types($centro_id, $source_aulario_id);
 if (!is_array($menuTypes) || count($menuTypes) === 0) {
 	$menuTypes = $defaultMenuTypes;
+	db_set_comedor_menu_types($centro_id, $source_aulario_id, $menuTypes);
 }
 
 $menuTypeIds = [];
@@ -71,10 +65,9 @@ if (!in_array($menuTypeId, $menuTypeIds, true)) {
 	$menuTypeId = $menuTypeIds[0] ?? "basal";
 }
 
-$ym = $dateObj->format("Y-m");
+$ym  = $dateObj->format("Y-m");
 $day = $dateObj->format("d");
-$baseDir = "/DATA/entreaulas/Centros/$centro_id/Aularios/$source_aulario_id/Comedor/$ym/$day";
-$dataPath = "$baseDir/_datos.json";
+
 
 function blank_menu()
 {
@@ -91,11 +84,9 @@ $menuData = [
 	"date" => $date,
 	"menus" => []
 ];
-if (file_exists($dataPath)) {
-	$existing = json_decode(file_get_contents($dataPath), true);
-	if (is_array($existing)) {
-		$menuData = array_merge($menuData, $existing);
-	}
+$existing = db_get_comedor_entry($centro_id, $source_aulario_id, $ym, $day);
+if (is_array($existing) && !empty($existing)) {
+	$menuData = array_merge($menuData, $existing);
 }
 if (!isset($menuData["menus"][$menuTypeId])) {
 	$menuData["menus"][$menuTypeId] = blank_menu();
@@ -251,14 +242,11 @@ if ($_SERVER["REQUEST_METHOD"] === "POST" && $canEdit) {
 		if ($newId !== "" && $newLabel !== "") {
 			$exists = false;
 			foreach ($menuTypes as $t) {
-				if (($t["id"] ?? "") === $newId) {
-					$exists = true;
-					break;
-				}
+				if (($t["id"] ?? "") === $newId) { $exists = true; break; }
 			}
 			if (!$exists) {
 				$menuTypes[] = ["id" => $newId, "label" => $newLabel, "color" => $newColor];
-				file_put_contents($menuTypesPath, json_encode($menuTypes, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
+				db_set_comedor_menu_types($centro_id, $source_aulario_id, $menuTypes);
 				header("Location: /entreaulas/comedor.php?aulario=" . urlencode($aulario_id) . "&date=" . urlencode($date) . "&menu=" . urlencode($newId));
 				exit;
 			}
@@ -268,19 +256,10 @@ if ($_SERVER["REQUEST_METHOD"] === "POST" && $canEdit) {
 	if ($action === "delete_type") {
 		$deleteId = safe_id_segment(trim($_POST["delete_type_id"] ?? ""));
 		if ($deleteId !== "") {
-			$deleted = false;
-			$newMenuTypes = [];
-			foreach ($menuTypes as $t) {
-				if (($t["id"] ?? "") === $deleteId) {
-					$deleted = true;
-				} else {
-					$newMenuTypes[] = $t;
-				}
-			}
-			if ($deleted) {
+			$newMenuTypes = array_values(array_filter($menuTypes, fn($t) => ($t["id"] ?? "") !== $deleteId));
+			if (count($newMenuTypes) !== count($menuTypes)) {
 				$menuTypes = $newMenuTypes;
-				file_put_contents($menuTypesPath, json_encode($menuTypes, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-				// Redirect to the first available menu type or default
+				db_set_comedor_menu_types($centro_id, $source_aulario_id, $menuTypes);
 				$redirectMenuId = !empty($menuTypes) ? $menuTypes[0]["id"] : "basal";
 				header("Location: /entreaulas/comedor.php?aulario=" . urlencode($aulario_id) . "&date=" . urlencode($date) . "&menu=" . urlencode($redirectMenuId));
 				exit;
@@ -296,15 +275,12 @@ if ($_SERVER["REQUEST_METHOD"] === "POST" && $canEdit) {
 			foreach ($menuTypes as &$t) {
 				if (($t["id"] ?? "") === $renameId) {
 					$t["label"] = $newLabel;
-					if ($newColor !== "") {
-						$t["color"] = $newColor;
-					}
+					if ($newColor !== "") { $t["color"] = $newColor; }
 					break;
 				}
 			}
-			// Clean up the reference to avoid accidental usage after the loop
 			unset($t);
-			file_put_contents($menuTypesPath, json_encode($menuTypes, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
+			db_set_comedor_menu_types($centro_id, $source_aulario_id, $menuTypes);
 			header("Location: /entreaulas/comedor.php?aulario=" . urlencode($aulario_id) . "&date=" . urlencode($date) . "&menu=" . urlencode($renameId));
 			exit;
 		}
@@ -316,23 +292,19 @@ if ($_SERVER["REQUEST_METHOD"] === "POST" && $canEdit) {
 			$menuData["menus"][$menuTypeId] = blank_menu();
 		}
 
+		// Pictogram images still stored on filesystem in Comedor dir
+		$baseDir = "/DATA/entreaulas/Centros/$centro_id/Aularios/$source_aulario_id/Comedor/$ym/$day";
 		$plates = ["primero", "segundo", "postre"];
 		foreach ($plates as $plate) {
 			$name = trim($_POST["name_" . $plate] ?? "");
 			$menuData["menus"][$menuTypeId]["plates"][$plate]["name"] = $name;
-
 			$pictUpload = handle_image_upload("pictogram_file_" . $plate, $menuTypeId . "_" . $plate . "_pict", $baseDir, $uploadErrors);
-
 			if ($pictUpload !== null) {
 				$menuData["menus"][$menuTypeId]["plates"][$plate]["pictogram"] = $pictUpload;
 			}
-
 		}
 
-		if (!is_dir($baseDir)) {
-			mkdir($baseDir, 0777, true);
-		}
-		file_put_contents($dataPath, json_encode($menuData, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
+		db_set_comedor_entry($centro_id, $source_aulario_id, $ym, $day, $menuData);
 		$saveNotice = "Menú guardado correctamente.";
 	}
 }
@@ -359,11 +331,10 @@ foreach ($userAulas as $aulaId) {
 	if ($aulaIdSafe === "") {
 		continue;
 	}
-	$aulaPath = "/DATA/entreaulas/Centros/$centro_id/Aularios/$aulaIdSafe.json";
-	$aulaData = file_exists($aulaPath) ? json_decode(file_get_contents($aulaPath), true) : null;
+	$aulaData = db_get_aulario($centro_id, $aulaIdSafe);
 	$aulaOptions[] = [
-		"id" => $aulaIdSafe,
-		"name" => $aulaData["name"] ?? $aulaIdSafe
+		"id"   => $aulaIdSafe,
+		"name" => $aulaData["name"] ?? $aulaIdSafe,
 	];
 }
 require_once "_incl/pre-body.php";
diff --git a/public_html/aulatek/index.php b/public_html/aulatek/index.php
old mode 100755
new mode 100644
index ce0271a..09e12d7
--- a/public_html/aulatek/index.php
+++ b/public_html/aulatek/index.php
@@ -2,30 +2,29 @@
 require_once "_incl/auth_redir.php";
 require_once "_incl/pre-body.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 ?>
 <div class="card pad">
     <div>
-        <h1 class="card-title">¡Hola, <?php echo $_SESSION["auth_data"]["display_name"];?>!</h1>
+        <h1 class="card-title">¡Hola, <?php echo htmlspecialchars($_SESSION["auth_data"]["display_name"]); ?>!</h1>
         <span>
             Bienvenidx a la plataforma de gestión de aularios conectados. Desde aquí podrás administrar los aularios asociados a tu cuenta.
         </span>
     </div>
 </div>
 <div id="grid">
-    <?php $user_data = $_SESSION["auth_data"];
+    <?php
+    $user_data = $_SESSION["auth_data"];
     $centro_id = safe_centro_id($user_data["entreaulas"]["centro"] ?? "");
-    foreach ($user_data["entreaulas"]["aulas"] as $aulario_id) {
+    $user_aulas = $user_data["entreaulas"]["aulas"] ?? [];
+    foreach ($user_aulas as $aulario_id) {
         $aulario_id = safe_id_segment($aulario_id);
         if ($aulario_id === "") {
             continue;
         }
-        $aulario_path = safe_aulario_config_path($centro_id, $aulario_id);
-        if (!$aulario_path || !file_exists($aulario_path)) {
-            continue;
-        }
-        $aulario = json_decode(file_get_contents($aulario_path), true);
-        if (!is_array($aulario)) {
+        $aulario = db_get_aulario($centro_id, $aulario_id);
+        if (!$aulario) {
             continue;
         }
         $aulario_name = $aulario["name"] ?? $aulario_id;
@@ -61,7 +60,6 @@ require_once "../_incl/tools.security.php";
     }
 </style>
 
-
 <script>
     var msnry = new Masonry('#grid', {
         "columnWidth": 250,
@@ -69,10 +67,7 @@ require_once "../_incl/tools.security.php";
         "gutter": 10,
         "transitionDuration": 0
     });
-    setInterval(() => {
-        msnry.layout()
-    }, 1000);
-    msnry.layout()
+    setTimeout(() => { msnry.layout() }, 250);
+    setInterval(() => { msnry.layout() }, 1000);
 </script>
-
 <?php require_once "_incl/post-body.php"; ?>
diff --git a/public_html/aulatek/paneldiario.php b/public_html/aulatek/paneldiario.php
index e11a5f3..056229a 100755
--- a/public_html/aulatek/paneldiario.php
+++ b/public_html/aulatek/paneldiario.php
@@ -1,6 +1,7 @@
 <?php
 require_once "_incl/auth_redir.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 ini_set("display_errors", "0");
 
 // Funciones auxiliares para el diario
@@ -784,12 +785,10 @@ switch ($view_action) {
     $source_aulario_id = $aulario_id;
     $is_shared = false;
     if ($aulario_id !== "" && $centro_id !== "") {
-      $aulario_path = safe_aulario_config_path($centro_id, $aulario_id);
-      $aulario = ($aulario_path && file_exists($aulario_path)) ? json_decode(file_get_contents($aulario_path), true) : null;
+      $aulario = db_get_aulario($centro_id, $aulario_id);
       if ($aulario && !empty($aulario["shared_comedor_from"])) {
         $shared_from = safe_id_segment($aulario["shared_comedor_from"]);
-        $shared_aulario_path = safe_aulario_config_path($centro_id, $shared_from);
-        if ($shared_aulario_path && file_exists($shared_aulario_path)) {
+        if (db_get_aulario($centro_id, $shared_from)) {
           $source_aulario_id = $shared_from;
           $is_shared = true;
         }
@@ -800,13 +799,12 @@ switch ($view_action) {
     $dateObj = DateTime::createFromFormat("Y-m-d", $dateParam) ?: new DateTime();
     $date = $dateObj->format("Y-m-d");
 
-    $menuTypesPath = ($centro_id !== '' && $source_aulario_id !== '') ? "/DATA/entreaulas/Centros/$centro_id/Aularios/$source_aulario_id/Comedor-MenuTypes.json" : "";
     $defaultMenuTypes = [
       ["id" => "basal", "label" => "Menú basal", "color" => "#0d6efd"],
       ["id" => "vegetariano", "label" => "Menú vegetariano", "color" => "#198754"],
       ["id" => "alergias", "label" => "Menú alergias", "color" => "#dc3545"],
     ];
-    $menuTypes = ($menuTypesPath !== '' && file_exists($menuTypesPath)) ? json_decode(@file_get_contents($menuTypesPath), true) : null;
+    $menuTypes = ($centro_id !== '' && $source_aulario_id !== '') ? db_get_comedor_menu_types($centro_id, $source_aulario_id) : [];
     if (!is_array($menuTypes) || count($menuTypes) === 0) {
       $menuTypes = $defaultMenuTypes;
     }
@@ -822,17 +820,13 @@ switch ($view_action) {
       $menuTypeId = $menuTypeIds[0] ?? "basal";
     }
 
-    $ym = $dateObj->format("Y-m");
+    $ym  = $dateObj->format("Y-m");
     $day = $dateObj->format("d");
-    $dataPath = ($centro_id !== '' && $source_aulario_id !== '') ? "/DATA/entreaulas/Centros/$centro_id/Aularios/$source_aulario_id/Comedor/$ym/$day/_datos.json" : "";
 
-    $menuData = [
-      "date" => $date,
-      "menus" => []
-    ];
-    if ($dataPath !== '' && file_exists($dataPath)) {
-      $existing = json_decode(file_get_contents($dataPath), true);
-      if (is_array($existing)) {
+    $menuData = ["date" => $date, "menus" => []];
+    if ($centro_id !== '' && $source_aulario_id !== '') {
+      $existing = db_get_comedor_entry($centro_id, $source_aulario_id, $ym, $day);
+      if (!empty($existing)) {
         $menuData = array_merge($menuData, $existing);
       }
     }
diff --git a/public_html/aulatek/proyectos.php b/public_html/aulatek/proyectos.php
index 7ff347c..d68606b 100644
--- a/public_html/aulatek/proyectos.php
+++ b/public_html/aulatek/proyectos.php
@@ -1,6 +1,7 @@
 <?php
 require_once "_incl/auth_redir.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 if (in_array("entreaulas:docente", $_SESSION["auth_data"]["permissions"] ?? []) === false) {
   header("HTTP/1.1 403 Forbidden");
@@ -23,8 +24,7 @@ if ($aulario_id === "" || $centro_id === "") {
   exit;
 }
 
-$aulario_path = "/DATA/entreaulas/Centros/$centro_id/Aularios/$aulario_id.json";
-$aulario = file_exists($aulario_path) ? json_decode(file_get_contents($aulario_path), true) : null;
+$aulario = db_get_aulario($centro_id, $aulario_id);
 
 $proyectos_dir = "/DATA/entreaulas/Centros/$centro_id/Proyectos";
 if (!is_dir($proyectos_dir)) {
@@ -71,16 +71,6 @@ function safe_join_file($base_dir, $filename)
   return rtrim($base_dir, '/') . '/' . $safe_name;
 }
 
-function safe_aulario_config_path($centro_id, $aulario_id)
-{
-  $safe_centro = safe_path_segment($centro_id);
-  $safe_aulario = safe_path_segment($aulario_id);
-  if ($safe_centro === '' || $safe_aulario === '') {
-    return null;
-  }
-  return "/DATA/entreaulas/Centros/$safe_centro/Aularios/$safe_aulario.json";
-}
-
 function sanitize_html($html)
 {
   $html = trim($html ?? "");
@@ -459,23 +449,18 @@ if ($_SERVER["REQUEST_METHOD"] === "POST") {
   }
 
   if ($action === "share_project") {
-    $project_id = safe_path_segment($_POST["project_id"] ?? "");
+    $project_id    = safe_path_segment($_POST["project_id"] ?? "");
     $target_aulario = safe_path_segment($_POST["target_aulario"] ?? "");
 
     if ($project_id !== "" && $target_aulario !== "" && $target_aulario !== $aulario_id) {
-      // Only allow sharing local projects
       $is_local_project = (load_project($proyectos_dir, $project_id) !== null);
       if (!$is_local_project) {
         $error = "No se puede compartir un proyecto ajeno.";
       } else {
-        $target_config_path = safe_aulario_config_path($centro_id, $target_aulario);
-        if ($target_config_path === null || !file_exists($target_config_path)) {
+        $target_config = db_get_aulario($centro_id, $target_aulario);
+        if ($target_config === null) {
           $error = "Aulario de destino no encontrado.";
         } else {
-          $target_config = json_decode(file_get_contents($target_config_path), true);
-          if (!is_array($target_config)) {
-            $target_config = [];
-          }
           if (!isset($target_config["linked_projects"]) || !is_array($target_config["linked_projects"])) {
             $target_config["linked_projects"] = [];
           }
@@ -494,13 +479,23 @@ if ($_SERVER["REQUEST_METHOD"] === "POST") {
           } else {
             $target_config["linked_projects"][] = [
               "source_aulario" => $aulario_id,
-              "project_id" => $project_id,
-              "permission" => "request_edit"
+              "project_id"     => $project_id,
+              "permission"     => "request_edit",
             ];
             $message = "Proyecto compartido correctamente.";
           }
 
-          file_put_contents($target_config_path, json_encode($target_config, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
+          // Save back: build extra JSON excluding standard fields
+          $extra_skip   = ['name', 'icon'];
+          $extra        = [];
+          foreach ($target_config as $k => $v) {
+            if (!in_array($k, $extra_skip, true)) {
+              $extra[$k] = $v;
+            }
+          }
+          db()->prepare(
+            "UPDATE aularios SET extra = ? WHERE centro_id = ? AND aulario_id = ?"
+          )->execute([json_encode($extra, JSON_UNESCAPED_UNICODE), $centro_id, $target_aulario]);
         }
       }
     }
@@ -1570,10 +1565,9 @@ $view = $current_project ? "project" : "list";
                 <path d="M18,16.08C17.24,16.08 16.56,16.38 16.04,16.85L8.91,12.7C8.96,12.47 9,12.24 9,12C9,11.76 8.96,11.53 8.91,11.3L15.96,7.19C16.5,7.69 17.21,8 18,8A3,3 0 0,0 21,5A3,3 0 0,0 18,2A3,3 0 0,0 15,5C15,5.24 15.04,5.47 15.09,5.7L8.04,9.81C7.5,9.31 6.79,9 6,9A3,3 0 0,0 3,12A3,3 0 0,0 6,15C6.79,15 7.5,14.69 8.04,14.19L15.16,18.34C15.11,18.55 15.08,18.77 15.08,19C15.08,20.61 16.39,21.91 18,21.91C19.61,21.91 20.92,20.61 20.92,19A2.92,2.92 0 0,0 18,16.08Z" />
               </svg>
               <?php
-              $source_aulario_path = safe_aulario_config_path($centro_id, $source_aulario_for_project);
               $source_aulario_name = "";
-              if ($source_aulario_path && file_exists($source_aulario_path)) {
-                $source_aulario_data = json_decode(file_get_contents($source_aulario_path), true);
+              $source_aulario_data = db_get_aulario($centro_id, $source_aulario_for_project);
+              if ($source_aulario_data) {
                 $source_aulario_name = $source_aulario_data["name"] ?? "";
               }
               ?>
@@ -1636,27 +1630,14 @@ $view = $current_project ? "project" : "list";
               <?php
               function list_aularios($centro_id)
               {
-                $aularios_dir = "/DATA/entreaulas/Centros/$centro_id/Aularios";
+                $aularios_db = db_get_aularios($centro_id);
                 $aularios = [];
-                if (is_dir($aularios_dir)) {
-                  $entries = scandir($aularios_dir);
-                  foreach ($entries as $entry) {
-                    if ($entry === "." || $entry === "..") {
-                      continue;
-                    }
-                    $aulario_path = "$aularios_dir/$entry";
-                    if (is_dir($aulario_path)) {
-                      $config_file = "$aulario_path.json";
-                      if (file_exists($config_file)) {
-                        $config = json_decode(file_get_contents($config_file), true);
-                        $aularios[] = [
-                          "id" => $entry,
-                          "name" => $config["name"] ?? "Aulario Desconocido",
-                          "linked_projects" => $config["linked_projects"] ?? []
-                        ];
-                      }
-                    }
-                  }
+                foreach ($aularios_db as $aid => $adata) {
+                  $aularios[] = [
+                    "id"              => $aid,
+                    "name"            => $adata["name"] ?? "Aulario Desconocido",
+                    "linked_projects" => $adata["linked_projects"] ?? [],
+                  ];
                 }
                 return $aularios;
               }
@@ -1918,10 +1899,8 @@ $view = $current_project ? "project" : "list";
       <div id="grid">
         <?php foreach ($pending_changes as $change):
           $requesting_aulario = $change["requested_by_aulario"] ?? "Desconocido";
-          // Get requesting aulario name
           $requesting_aulario = safe_path_segment($requesting_aulario);
-          $req_aul_path = safe_aulario_config_path($centro_id, $requesting_aulario);
-          $req_aul_data = ($req_aul_path && file_exists($req_aul_path)) ? json_decode(file_get_contents($req_aul_path), true) : null;
+          $req_aul_data = db_get_aulario($centro_id, $requesting_aulario);
           $req_aul_name = $req_aul_data["name"] ?? $requesting_aulario;
           $req_persona_name = $change["requested_by_persona_name"] ?? "Desconocido";
         ?>
diff --git a/public_html/aulatek/supercafe.php b/public_html/aulatek/supercafe.php
index e1d0355..1b53a4a 100644
--- a/public_html/aulatek/supercafe.php
+++ b/public_html/aulatek/supercafe.php
@@ -1,6 +1,7 @@
 <?php
 require_once "_incl/auth_redir.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 if (!in_array('supercafe:access', $_SESSION['auth_data']['permissions'] ?? [])) {
     header('HTTP/1.1 403 Forbidden');
@@ -8,28 +9,23 @@ if (!in_array('supercafe:access', $_SESSION['auth_data']['permissions'] ?? []))
 }
 
 /**
- * Load personas from the existing Alumnos system.
- * Returns array keyed by "{aulario_id}:{alumno_name}" with
- * ['Nombre', 'Region' (aulario display name), 'AularioID', 'HasPhoto'] entries.
+ * Load personas from the Alumnos filesystem (photos still on disk).
+ * Returns array keyed by "{aulario_id}:{alumno_name}".
  */
 function sc_load_personas_from_alumnos($centro_id)
 {
-    $aularios_path = "/DATA/entreaulas/Centros/$centro_id/Aularios";
-    $personas = [];
-    if (!is_dir($aularios_path)) {
-        return $personas;
-    }
-    foreach (glob("$aularios_path/*.json") ?: [] as $aulario_file) {
-        $aulario_id   = basename($aulario_file, '.json');
-        $aulario_data = json_decode(file_get_contents($aulario_file), true);
+    $aularios     = db_get_aularios($centro_id);
+    $personas     = [];
+    $aularios_dir = "/DATA/entreaulas/Centros/$centro_id/Aularios";
+    foreach ($aularios as $aulario_id => $aulario_data) {
         $aulario_name = $aulario_data['name'] ?? $aulario_id;
-        $alumnos_path = "$aularios_path/$aulario_id/Alumnos";
+        $alumnos_path = "$aularios_dir/$aulario_id/Alumnos";
         if (!is_dir($alumnos_path)) {
             continue;
         }
         foreach (glob("$alumnos_path/*/", GLOB_ONLYDIR) ?: [] as $alumno_dir) {
             $alumno_name = basename($alumno_dir);
-            $key = $aulario_id . ':' . $alumno_name;
+            $key         = $aulario_id . ':' . $alumno_name;
             $personas[$key] = [
                 'Nombre'    => $alumno_name,
                 'Region'    => $aulario_name,
@@ -62,7 +58,6 @@ if ($centro_id === '') {
     exit;
 }
 
-define('SC_DATA_DIR', "/DATA/entreaulas/Centros/$centro_id/SuperCafe/Comandas");
 define('SC_MAX_DEBTS', 3);
 
 $estados_colores = [
@@ -81,20 +76,15 @@ if ($_SERVER['REQUEST_METHOD'] === 'POST' && $can_edit) {
     $action = $_POST['action'] ?? '';
 
     if ($action === 'change_status') {
-        $order_id  = safe_id($_POST['order_id'] ?? '');
+        $order_id   = safe_id($_POST['order_id'] ?? '');
         $new_status = $_POST['status'] ?? '';
         if ($order_id !== '' && array_key_exists($new_status, $estados_colores)) {
-            $order_file = SC_DATA_DIR . '/' . $order_id . '.json';
-            if (is_readable($order_file)) {
-                $data = json_decode(file_get_contents($order_file), true);
-                if (is_array($data)) {
-                    $data['Estado'] = $new_status;
-                    file_put_contents(
-                        $order_file,
-                        json_encode($data, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE),
-                        LOCK_EX
-                    );
-                }
+            $row = db_get_supercafe_order($centro_id, $order_id);
+            if ($row) {
+                db_upsert_supercafe_order(
+                    $centro_id, $order_id,
+                    $row['fecha'], $row['persona'], $row['comanda'], $row['notas'], $new_status
+                );
             }
         }
         header('Location: /entreaulas/supercafe.php');
@@ -104,34 +94,30 @@ if ($_SERVER['REQUEST_METHOD'] === 'POST' && $can_edit) {
     if ($action === 'delete') {
         $order_id = safe_id($_POST['order_id'] ?? '');
         if ($order_id !== '') {
-            $order_file = SC_DATA_DIR . '/' . $order_id . '.json';
-            if (is_file($order_file)) {
-                unlink($order_file);
-            }
+            db()->prepare('DELETE FROM supercafe_orders WHERE centro_id = ? AND order_ref = ?')
+               ->execute([$centro_id, $order_id]);
         }
         header('Location: /entreaulas/supercafe.php');
         exit;
     }
 }
 
-// Load all orders
+// Load all orders from DB
+$db_orders = db_get_supercafe_orders($centro_id);
 $orders = [];
-if (is_dir(SC_DATA_DIR)) {
-    $files = glob(SC_DATA_DIR . '/*.json') ?: [];
-    foreach ($files as $file) {
-        $data = json_decode(file_get_contents($file), true);
-        if (!is_array($data)) {
-            continue;
-        }
-        $data['_id'] = basename($file, '.json');
-        $orders[] = $data;
-    }
+foreach ($db_orders as $row) {
+    $orders[] = [
+        '_id'    => $row['order_ref'],
+        'Fecha'  => $row['fecha'],
+        'Persona'=> $row['persona'],
+        'Comanda'=> $row['comanda'],
+        'Notas'  => $row['notas'],
+        'Estado' => $row['estado'],
+    ];
 }
 
 // Sort newest first (by Fecha desc)
-usort($orders, function ($a, $b) {
-    return strcmp($b['Fecha'] ?? '', $a['Fecha'] ?? '');
-});
+usort($orders, fn($a, $b) => strcmp($b['Fecha'] ?? '', $a['Fecha'] ?? ''));
 
 $orders_active = array_filter($orders, fn($o) => ($o['Estado'] ?? '') !== 'Deuda');
 $orders_deuda  = array_filter($orders, fn($o) => ($o['Estado'] ?? '') === 'Deuda');
@@ -139,6 +125,7 @@ $orders_deuda  = array_filter($orders, fn($o) => ($o['Estado'] ?? '') === 'Deuda
 require_once "_incl/pre-body.php";
 ?>
 
+
 <div class="card pad">
     <div style="display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 10px;">
         <h1 style="margin: 0;">SuperCafe – Cafetería</h1>
diff --git a/public_html/aulatek/supercafe_edit.php b/public_html/aulatek/supercafe_edit.php
index ded87ea..2e187b7 100644
--- a/public_html/aulatek/supercafe_edit.php
+++ b/public_html/aulatek/supercafe_edit.php
@@ -1,6 +1,7 @@
 <?php
 require_once "_incl/auth_redir.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 if (!in_array('supercafe:edit', $_SESSION['auth_data']['permissions'] ?? [])) {
     header('HTTP/1.1 403 Forbidden');
@@ -15,42 +16,30 @@ if ($centro_id === '') {
     exit;
 }
 
-$sc_base = "/DATA/entreaulas/Centros/$centro_id/SuperCafe";
-define('SC_DATA_DIR', "$sc_base/Comandas");
 define('SC_MAX_DEBTS', 3);
 
 $valid_statuses = ['Pedido', 'En preparación', 'Listo', 'Entregado', 'Deuda'];
 
 /**
- * Load personas from the existing Alumnos system (alumnos.php).
- * Returns array keyed by "{aulario_id}:{alumno_name}" with
- * ['Nombre', 'Region' (aulario display name), 'AularioID'] entries.
- * Groups are sorted by aulario name, alumnos sorted alphabetically.
+ * Load personas from the Alumnos filesystem (photos still on disk).
+ * Returns array keyed by "{aulario_id}:{alumno_name}".
  */
 function sc_load_personas_from_alumnos($centro_id)
 {
-    $aularios_path = "/DATA/entreaulas/Centros/$centro_id/Aularios";
-    $personas = [];
-    if (!is_dir($aularios_path)) {
-        return $personas;
-    }
-    $aulario_files = glob("$aularios_path/*.json") ?: [];
-    foreach ($aulario_files as $aulario_file) {
-        $aulario_id   = basename($aulario_file, '.json');
-        $aulario_data = json_decode(file_get_contents($aulario_file), true);
+    $aularios     = db_get_aularios($centro_id);
+    $personas     = [];
+    $aularios_dir = "/DATA/entreaulas/Centros/$centro_id/Aularios";
+    foreach ($aularios as $aulario_id => $aulario_data) {
         $aulario_name = $aulario_data['name'] ?? $aulario_id;
-        $alumnos_path = "$aularios_path/$aulario_id/Alumnos";
+        $alumnos_path = "$aularios_dir/$aulario_id/Alumnos";
         if (!is_dir($alumnos_path)) {
             continue;
         }
         $alumno_dirs = glob("$alumnos_path/*/", GLOB_ONLYDIR) ?: [];
-        usort($alumno_dirs, function ($a, $b) {
-            return strcasecmp(basename($a), basename($b));
-        });
+        usort($alumno_dirs, fn($a, $b) => strcasecmp(basename($a), basename($b)));
         foreach ($alumno_dirs as $alumno_dir) {
             $alumno_name = basename($alumno_dir);
-            // Key uses ':' as separator; safe_id_segment chars [A-Za-z0-9_-] exclude ':'
-            $key = $aulario_id . ':' . $alumno_name;
+            $key         = $aulario_id . ':' . $alumno_name;
             $personas[$key] = [
                 'Nombre'    => $alumno_name,
                 'Region'    => $aulario_name,
@@ -62,43 +51,14 @@ function sc_load_personas_from_alumnos($centro_id)
     return $personas;
 }
 
-function sc_load_menu($sc_base)
-{
-    $path = "$sc_base/Menu.json";
-    if (!file_exists($path)) {
-        return [];
-    }
-    $data = json_decode(file_get_contents($path), true);
-    return is_array($data) ? $data : [];
-}
-
-function sc_count_debts($persona_key)
-{
-    if (!is_dir(SC_DATA_DIR)) {
-        return 0;
-    }
-    $count = 0;
-    foreach (glob(SC_DATA_DIR . '/*.json') ?: [] as $file) {
-        $data = json_decode(file_get_contents($file), true);
-        if (is_array($data)
-            && ($data['Persona'] ?? '') === $persona_key
-            && ($data['Estado'] ?? '') === 'Deuda') {
-            $count++;
-        }
-    }
-    return $count;
-}
-
 // Determine if creating or editing
 $order_id = safe_id($_GET['id'] ?? '');
 $is_new   = $order_id === '';
 if ($is_new) {
-    $raw_id   = uniqid('sc', true);
-    $order_id = preg_replace('/[^a-zA-Z0-9_-]/', '', $raw_id);
+    $order_id = db_next_supercafe_ref($centro_id);
 }
 
-$order_file = SC_DATA_DIR . '/' . $order_id . '.json';
-
+// Load existing order from DB (or defaults)
 $order_data = [
     'Fecha'   => date('Y-m-d'),
     'Persona' => '',
@@ -106,15 +66,21 @@ $order_data = [
     'Notas'   => '',
     'Estado'  => 'Pedido',
 ];
-if (!$is_new && is_readable($order_file)) {
-    $existing = json_decode(file_get_contents($order_file), true);
-    if (is_array($existing)) {
-        $order_data = array_merge($order_data, $existing);
+if (!$is_new) {
+    $existing = db_get_supercafe_order($centro_id, $order_id);
+    if ($existing) {
+        $order_data = [
+            'Fecha'   => $existing['fecha'],
+            'Persona' => $existing['persona'],
+            'Comanda' => $existing['comanda'],
+            'Notas'   => $existing['notas'],
+            'Estado'  => $existing['estado'],
+        ];
     }
 }
 
 $personas = sc_load_personas_from_alumnos($centro_id);
-$menu     = sc_load_menu($sc_base);
+$menu     = db_get_supercafe_menu($centro_id);
 
 // Group personas by aulario for the optgroup picker
 $personas_by_aulario = [];
@@ -133,11 +99,9 @@ if ($_SERVER['REQUEST_METHOD'] === 'POST') {
         $estado = 'Pedido';
     }
 
-    // Validar persona
     if ($persona_key === '' || (!empty($personas) && !array_key_exists($persona_key, $personas))) {
         $error = '¡Hay que elegir una persona válida!';
     } else {
-        // Construir comanda desde los campos de categoría visual
         $comanda_parts = [];
         if (!empty($menu)) {
             foreach ($menu as $category => $items) {
@@ -152,48 +116,28 @@ if ($_SERVER['REQUEST_METHOD'] === 'POST') {
                 $comanda_parts[] = $manual;
             }
         }
-        $comanda_str = implode(', ', $comanda_parts);
-
-        // Comprobar deudas
-        $prev_persona = $order_data['Persona'] ?? '';
+        $comanda_str  = implode(', ', $comanda_parts);
+        $prev_persona = $order_data['Persona'];
         if ($is_new || $prev_persona !== $persona_key) {
-            $debt_count = sc_count_debts($persona_key);
+            $debt_count = db_supercafe_count_debts($centro_id, $persona_key);
             if ($debt_count >= SC_MAX_DEBTS) {
                 $error = 'Esta persona tiene ' . $debt_count . ' comandas en deuda. No se puede realizar el pedido.';
             }
         }
-
         if ($error === '') {
-            $new_data = [
-                'Fecha'   => date('Y-m-d'),
-                'Persona' => $persona_key,
-                'Comanda' => $comanda_str,
-                'Notas'   => $notas,
-                'Estado'  => $is_new ? 'Pedido' : $estado,
-            ];
-
-            if (!is_dir(SC_DATA_DIR)) {
-                mkdir(SC_DATA_DIR, 0755, true);
-            }
-
-            $tmp   = SC_DATA_DIR . '/.' . $order_id . '.tmp';
-            $bytes = file_put_contents(
-                $tmp,
-                json_encode($new_data, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE),
-                LOCK_EX
+            db_upsert_supercafe_order(
+                $centro_id, $order_id,
+                date('Y-m-d'), $persona_key, $comanda_str, $notas,
+                $is_new ? 'Pedido' : $estado
             );
-            if ($bytes === false || !rename($tmp, $order_file)) {
-                @unlink($tmp);
-                $error = 'Error al guardar la comanda.';
-            } else {
-                header('Location: /entreaulas/supercafe.php');
-                exit;
-            }
+            header('Location: /entreaulas/supercafe.php');
+            exit;
         }
     }
 }
 
 require_once "_incl/pre-body.php";
+
 ?>
 
 <h1>Comanda <code><?= htmlspecialchars($order_id) ?></code></h1>
diff --git a/public_html/club/cal.php b/public_html/club/cal.php
index 97ba209..d67ebb4 100755
--- a/public_html/club/cal.php
+++ b/public_html/club/cal.php
@@ -1,10 +1,11 @@
 <?php
 require_once "../_incl/tools.session.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 ini_set("display_errors", 0);
 $file = Sf($_GET["f"]);
 $date = implode("/", array_reverse(explode("-", $file)));
-$val = json_decode(file_get_contents("/DATA/club/IMG/$file/data.json"), true);
+$val  = db_get_club_event($file);
 
 $fotos = glob("/DATA/club/IMG/$file/*/");
 
diff --git a/public_html/club/edit_data.php b/public_html/club/edit_data.php
index 1a7a9bc..4d516e6 100755
--- a/public_html/club/edit_data.php
+++ b/public_html/club/edit_data.php
@@ -1,19 +1,18 @@
 <?php
 ini_set("display_errors", 0);
+require_once "../_incl/db.php";
 $file = Sf($_GET["f"]);
 $date = implode("/", array_reverse(explode("-", $file)));
-$val = json_decode(file_get_contents("/DATA/club/IMG/$file/data.json"), true);
-$config = json_decode(file_get_contents("/DATA/club/config.json"), true);
-if(strtoupper($_POST["adminpw"]) == strtoupper($config["adminpw"] ?? "")) {
+$val  = db_get_club_event($file);
+$adminpw = db_get_config('club_adminpw', '');
+if (strtoupper($_POST["adminpw"] ?? '') === strtoupper($adminpw) && !empty($adminpw)) {
     $data = [
-            "title" => $_POST["title"],
-            "note" => $_POST["note"],
-            "mapa" => [
-                "url" => $_POST["mapa_url"]
-            ]
-        ];
+        "title" => $_POST["title"],
+        "note"  => $_POST["note"],
+        "mapa"  => ["url" => $_POST["mapa_url"]],
+    ];
     $file = $_POST["date"];
-    $val = file_put_contents("/DATA/club/IMG/$file/data.json", json_encode($data, JSON_UNESCAPED_SLASHES));
+    db_set_club_event($file, $data);
     header("Location: /club/");
     die();
 }
diff --git a/public_html/club/index.php b/public_html/club/index.php
index 167fd72..0dc861c 100755
--- a/public_html/club/index.php
+++ b/public_html/club/index.php
@@ -1,5 +1,6 @@
 <?php
 ini_set("display_errors", 0);
+require_once "../_incl/db.php";
 $files = glob("/DATA/club/IMG/*/");
 sort($files);
 $files = array_reverse($files);
@@ -17,7 +18,7 @@ require_once "../_incl/pre-body.php"; ?>
         <?php foreach ($files as $file) {
             $filenam = str_replace("/", "", str_replace("/DATA/club/IMG/", "", $file));
             $date = implode("/", array_reverse(explode("-", $filenam)));
-            $val = json_decode(file_get_contents($file . "data.json"), true)
+            $val = db_get_club_event($filenam);
                 ?>
 
             <li><a class="btn btn-secondary" href="cal.php?f=<?php echo $filenam; ?>"><b><?php echo $date; ?></b></a> -
diff --git a/public_html/club/upload/upload.php b/public_html/club/upload/upload.php
index 920456a..0811646 100755
--- a/public_html/club/upload/upload.php
+++ b/public_html/club/upload/upload.php
@@ -1,7 +1,8 @@
 <?php
 ini_set("display_errors", 1);
-$config = json_decode(file_get_contents("/DATA/club/config.json"), true);
-if (strtoupper($_GET["pw"]) != $config["uploadpw"]) {
+require_once "../../_incl/db.php";
+$uploadpw = db_get_config('club_uploadpw', '');
+if ($uploadpw === '' || strtoupper($_GET["pw"] ?? '') !== strtoupper($uploadpw)) {
     header("HTTP/1.1 401 Unauthorized");
     die();
 }
diff --git a/public_html/sysadmin/aularios.php b/public_html/sysadmin/aularios.php
index ba15ace..1a1651b 100644
--- a/public_html/sysadmin/aularios.php
+++ b/public_html/sysadmin/aularios.php
@@ -1,10 +1,11 @@
 <?php
 require_once "_incl/auth_redir.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 function safe_path_segment($value)
 {
-    $value = trim((string)$value);
+    $value = trim((string) $value);
     $value = str_replace(["\0", "/", "\\"], "", $value);
     $value = str_replace("..", "", $value);
     $value = basename($value);
@@ -18,417 +19,214 @@ $form_action = $_GET["form"] ?? "";
 switch ($form_action) {
     case "delete":
         $aulario_id = safe_path_segment(Sf($_POST["aulario_id"] ?? ""));
-        $centro_id = safe_path_segment(Sf($_POST["centro_id"] ?? ""));
-        $aulario_file = "/DATA/entreaulas/Centros/$centro_id/Aularios/$aulario_id.json";
-        if (!file_exists($aulario_file)) {
-            die("Aulario no encontrado.");
+        $centro_id  = safe_path_segment(Sf($_POST["centro_id"]  ?? ""));
+        if ($aulario_id === "" || $centro_id === "") {
+            die("Parámetros inválidos.");
         }
-        // Remove aulario directory and contents
+        // Remove from DB
+        db()->prepare("DELETE FROM aularios WHERE centro_id = ? AND aulario_id = ?")
+            ->execute([$centro_id, $aulario_id]);
+        // Remove comedor, diario, panel data
+        db()->prepare("DELETE FROM comedor_menu_types WHERE centro_id = ? AND aulario_id = ?")
+            ->execute([$centro_id, $aulario_id]);
+        db()->prepare("DELETE FROM comedor_entries WHERE centro_id = ? AND aulario_id = ?")
+            ->execute([$centro_id, $aulario_id]);
+        db()->prepare("DELETE FROM diario_entries WHERE centro_id = ? AND aulario_id = ?")
+            ->execute([$centro_id, $aulario_id]);
+        db()->prepare("DELETE FROM panel_alumno WHERE centro_id = ? AND aulario_id = ?")
+            ->execute([$centro_id, $aulario_id]);
+        // Remove filesystem directory with student photos
         $aulario_dir = "/DATA/entreaulas/Centros/$centro_id/Aularios/$aulario_id";
-        function rrmdir($dir) {
+        function rrmdir($dir)
+        {
             if (is_dir($dir)) {
-                $objects = scandir($dir);
-                foreach ($objects as $object) {
-                    if ($object != "." && $object != "..") {
-                        $obj_path = $dir . "/" . $object;
-                        if (is_dir($obj_path)) {
-                            rrmdir($obj_path);
-                        } else {
-                            unlink($obj_path);
-                        }
+                foreach (scandir($dir) as $object) {
+                    if ($object !== "." && $object !== "..") {
+                        $p = "$dir/$object";
+                        is_dir($p) ? rrmdir($p) : unlink($p);
                     }
                 }
                 rmdir($dir);
             }
         }
         rrmdir($aulario_dir);
-        // Remove aulario config file
-        unlink($aulario_file);
         header("Location: ?action=index");
         exit();
         break;
     case "create":
-        $user_data = $_SESSION["auth_data"];
-        $centro_id = safe_path_segment(Sf($_POST["centro"] ?? ""));
-        if (empty($centro_id) || !is_dir("/DATA/entreaulas/Centros/$centro_id")) {
+        $centro_id  = safe_path_segment(Sf($_POST["centro"]  ?? ""));
+        $aulario_id = strtolower(preg_replace("/[^a-zA-Z0-9_-]/", "_", Sf($_POST["name"] ?? "")));
+        if (empty($centro_id) || empty($aulario_id)) {
+            die("Datos incompletos.");
+        }
+        // Ensure centro exists in DB
+        $stmt = db()->prepare("SELECT id FROM centros WHERE centro_id = ?");
+        $stmt->execute([$centro_id]);
+        if (!$stmt->fetch()) {
             die("Centro no válido.");
         }
-        $aulario_id = strtolower(preg_replace("/[^a-zA-Z0-9_-]/", "_", Sf($_POST["name"] ?? "")));
-        $aulario_data = [
-            "name" => Sf($_POST["name"] ?? ""),
-            "icon" => Sf($_POST["icon"] ?? "/static/logo-entreaulas.png")
-        ];
-        // Make path recursive (mkdir -p equivalent)
-        @mkdir("/DATA/entreaulas/Centros/$centro_id/Aularios/", 0777, true);
-        @mkdir("/DATA/entreaulas/Centros/$centro_id/Aularios/$aulario_id/Proyectos/", 0777, true);
-        file_put_contents("/DATA/entreaulas/Centros/$centro_id/Aularios/$aulario_id.json", json_encode($aulario_data));
-        // Update user data
-        $_SESSION["auth_data"]["entreaulas"]["aulas"][] = $aulario_id;
+        db()->prepare(
+            "INSERT OR IGNORE INTO aularios (centro_id, aulario_id, name, icon) VALUES (?, ?, ?, ?)"
+        )->execute([
+            $centro_id, $aulario_id,
+            Sf($_POST["name"] ?? ""),
+            Sf($_POST["icon"] ?? "/static/logo-entreaulas.png"),
+        ]);
+        // Create Alumnos directory for photo-based features
+        @mkdir("/DATA/entreaulas/Centros/$centro_id/Aularios/$aulario_id/Proyectos/", 0755, true);
         header("Location: ?action=index");
         exit();
         break;
     case "save_edit":
         $aulario_id = safe_path_segment(Sf($_POST["aulario_id"] ?? ""));
-        $centro_id = safe_path_segment(Sf($_POST["centro_id"] ?? ""));
-        $aulario_file = "/DATA/entreaulas/Centros/$centro_id/Aularios/$aulario_id.json";
-        if (!file_exists($aulario_file)) {
+        $centro_id  = safe_path_segment(Sf($_POST["centro_id"]  ?? ""));
+        if ($aulario_id === "" || $centro_id === "") {
+            die("Parámetros inválidos.");
+        }
+        // Fetch existing extra data
+        $existing = db_get_aulario($centro_id, $aulario_id);
+        if ($existing === null) {
             die("Aulario no encontrado.");
         }
-        $aulario_data = json_decode(file_get_contents($aulario_file), true);
-        $aulario_data["name"] = Sf($_POST["name"] ?? "");
-        $aulario_data["icon"] = Sf($_POST["icon"] ?? "/static/logo-entreaulas.png");
-        
-        // Handle shared comedor configuration
-        $share_comedor_from = safe_path_segment(Sf($_POST["share_comedor_from"] ?? ""));
-        
-        if (!empty($share_comedor_from) && $share_comedor_from !== "none") {
-            $aulario_data["shared_comedor_from"] = $share_comedor_from;
-        } else {
-            unset($aulario_data["shared_comedor_from"]);
-        }
-        
-        // Handle linked projects configuration
-        $linked_projects = [];
-        $linked_aularios = $_POST["linked_aulario"] ?? [];
-        $linked_project_ids = $_POST["linked_project_id"] ?? [];
-        $linked_permissions = $_POST["linked_permission"] ?? [];
-        
-        for ($i = 0; $i < count($linked_aularios); $i++) {
-            $src_aul = safe_path_segment($linked_aularios[$i] ?? "");
-            $proj_id = safe_path_segment($linked_project_ids[$i] ?? "");
-            $perm = in_array(($linked_permissions[$i] ?? "read_only"), ["read_only", "request_edit", "full_edit"], true)
-                ? ($linked_permissions[$i] ?? "read_only")
-                : "read_only";
-            if (!empty($src_aul) && !empty($proj_id)) {
-                $linked_projects[] = [
-                    "source_aulario" => $src_aul,
-                    "project_id" => $proj_id,
-                    "permission" => $perm
-                ];
+        // Build extra JSON preserving any existing extra fields
+        $extra_skip = ['name', 'icon'];
+        $extra = [];
+        foreach ($existing as $k => $v) {
+            if (!in_array($k, $extra_skip, true)) {
+                $extra[$k] = $v;
             }
         }
-        
-        if (count($linked_projects) > 0) {
-            $aulario_data["linked_projects"] = $linked_projects;
-        } else {
-            unset($aulario_data["linked_projects"]);
+        // Update shared_comedor_from if posted
+        if (isset($_POST['shared_comedor_from'])) {
+            $extra['shared_comedor_from'] = Sf($_POST['shared_comedor_from']);
         }
-        @mkdir("/DATA/entreaulas/Centros/$centro_id/Aularios/$aulario_id/Proyectos/", 0777, true);
-        file_put_contents($aulario_file, json_encode($aulario_data, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-        header("Location: ?action=edit&aulario=" . urlencode($aulario_id) . "&centro=" . urlencode($centro_id) . "&saved=1");
+        db()->prepare(
+            "UPDATE aularios SET name = ?, icon = ?, extra = ? WHERE centro_id = ? AND aulario_id = ?"
+        )->execute([
+            Sf($_POST["name"] ?? ""),
+            Sf($_POST["icon"] ?? "/static/logo-entreaulas.png"),
+            json_encode($extra),
+            $centro_id,
+            $aulario_id,
+        ]);
+        header("Location: ?action=edit&aulario=" . urlencode($aulario_id) . "&centro=" . urlencode($centro_id) . "&_result=" . urlencode("Cambios guardados."));
         exit();
         break;
 }
 
-require_once "_incl/pre-body.php"; 
 $view_action = $_GET["action"] ?? "index";
 switch ($view_action) {
     case "new":
-        ?>
+        require_once "_incl/pre-body.php";
+        $centro_id   = safe_path_segment(Sf($_GET["centro"] ?? ""));
+        $all_centros = db_get_centro_ids();
+?>
 <div class="card pad">
     <div>
-        <h1 class="card-title">Nuevo Aulario</h1>
-        <span>
-            Aquí puedes crear un nuevo aulario para el centro que administras.
-        </span>
+        <h1>Nuevo Aulario</h1>
         <form method="post" action="?form=create">
             <div class="mb-3">
-                <label for="centro" class="form-label"><b>Centro:</b></label>
-                <select required id="centro" name="centro" class="form-select">
+                <label for="centro" class="form-label">Centro:</label>
+                <select id="centro" name="centro" class="form-select" required>
                     <option value="">-- Selecciona un centro --</option>
-                    <?php
-                    foreach (glob("/DATA/entreaulas/Centros/*", GLOB_ONLYDIR) as $centro_folder) {
-                        $centro_id = basename($centro_folder);
-                        $selected = ($centro_id == $_SESSION["auth_data"]["entreaulas"]["centro"]) ? "selected" : "";
-                        echo '<option value="' . htmlspecialchars($centro_id) . '" ' . $selected . '>' . htmlspecialchars($centro_id) . '</option>';
-                    }
-                    ?>
+                    <?php foreach ($all_centros as $cid): ?>
+                    <option value="<?= htmlspecialchars($cid) ?>" <?= $cid === $centro_id ? 'selected' : '' ?>><?= htmlspecialchars($cid) ?></option>
+                    <?php endforeach; ?>
                 </select>
             </div>
             <div class="mb-3">
-                <label for="name" class="form-label">Nombre del Aulario:</label>
-                <input required type="text" id="name" name="name" class="form-control" placeholder="Ej: Aulario Principal">
+                <label for="name" class="form-label">Nombre:</label>
+                <input required type="text" id="name" name="name" class="form-control" placeholder="Ej: Aula 1">
             </div>
             <div class="mb-3">
-                <label for="icon" class="form-label">Icono del Aulario (URL):</label>
-                <input type="text" id="icon" name="icon" class="form-control" placeholder="Ej: https://example.com/icon.png" value="/static/logo-entreaulas.png">
+                <label for="icon" class="form-label">URL del icono:</label>
+                <input type="url" id="icon" name="icon" class="form-control" value="/static/logo-entreaulas.png">
             </div>
             <button type="submit" class="btn btn-primary">Crear Aulario</button>
         </form>
     </div>
 </div>
-
 <?php
+        require_once "_incl/post-body.php";
         break;
     case "edit":
+        require_once "_incl/pre-body.php";
         $aulario_id = safe_path_segment(Sf($_GET["aulario"] ?? ""));
-        $centro_id = safe_path_segment(Sf($_GET["centro"] ?? ""));
-        $aulario_file = "/DATA/entreaulas/Centros/$centro_id/Aularios/$aulario_id.json";
-        if (!file_exists($aulario_file)) {
+        $centro_id  = safe_path_segment(Sf($_GET["centro"]  ?? ""));
+        $aulario    = db_get_aulario($centro_id, $aulario_id);
+        if (!$aulario) {
             die("Aulario no encontrado.");
         }
-        $aulario_data = json_decode(file_get_contents($aulario_file), true);
-        
-        // Get all aularios from the same centro for sharing options
-        $available_aularios = [];
-        $aularios_files = glob("/DATA/entreaulas/Centros/$centro_id/Aularios/*.json");
-        foreach ($aularios_files as $aul_file) {
-            $aul_id = basename($aul_file, ".json");
-            if ($aul_id !== $aulario_id) { // Don't allow sharing from itself
-                $aul_data = json_decode(file_get_contents($aul_file), true);
-                $available_aularios[$aul_id] = $aul_data['name'] ?? $aul_id;
-            }
-        }
-        
-        // Get available projects from other aularios
-        $available_projects_by_aulario = [];
-        foreach ($available_aularios as $aul_id => $aul_name) {
-            $proj_dir = "/DATA/entreaulas/Centros/$centro_id/Aularios/$aul_id/Proyectos";
-            if (is_dir($proj_dir)) {
-                $projects = [];
-                $files = glob("$proj_dir/*.json");
-                foreach ($files as $file) {
-                    $proj_data = json_decode(file_get_contents($file), true);
-                    // Only include root projects (no parent)
-                    if ($proj_data && ($proj_data["parent_id"] ?? null) === null) {
-                        $projects[] = [
-                            "id" => $proj_data["id"] ?? basename($file, ".json"),
-                            "name" => $proj_data["name"] ?? "Sin nombre"
-                        ];
-                    }
-                }
-                if (count($projects) > 0) {
-                    $available_projects_by_aulario[$aul_id] = $projects;
-                }
-            }
-        }
+        $other_aularios = db_get_aularios($centro_id);
 ?>
-<?php if (isset($_GET['saved'])): ?>
-<div class="alert alert-success">Cambios guardados correctamente.</div>
-<?php endif; ?>
 <div class="card pad">
     <div>
-        <h1 class="card-title">Editar Aulario: <?php echo htmlspecialchars($aulario_data['name'] ?? 'Sin Nombre'); ?></h1>
+        <h1>Aulario: <?= htmlspecialchars($aulario['name'] ?? $aulario_id) ?></h1>
         <form method="post" action="?form=save_edit">
+            <input type="hidden" name="aulario_id" value="<?= htmlspecialchars($aulario_id) ?>">
+            <input type="hidden" name="centro_id"  value="<?= htmlspecialchars($centro_id) ?>">
             <div class="mb-3">
-                <label for="name" class="form-label">Nombre del Aulario:</label>
-                <input required type="text" id="name" name="name" class="form-control" value="<?php echo htmlspecialchars($aulario_data['name'] ?? ''); ?>">
+                <label for="name" class="form-label">Nombre:</label>
+                <input required type="text" id="name" name="name" class="form-control" value="<?= htmlspecialchars($aulario['name'] ?? '') ?>">
             </div>
             <div class="mb-3">
-                <label for="icon" class="form-label">Icono del Aulario (URL):</label>
-                <input type="text" id="icon" name="icon" class="form-control" value="<?php echo htmlspecialchars($aulario_data['icon'] ?? '/static/iconexperience/blackboard.png'); ?>">
+                <label for="icon" class="form-label">URL del icono:</label>
+                <input type="text" id="icon" name="icon" class="form-control" value="<?= htmlspecialchars($aulario['icon'] ?? '') ?>">
             </div>
-            
-            <hr>
-            <h3>Compartir Menú Comedor</h3>
-            <p class="text-muted">Configura desde qué aulario compartir los datos del menú comedor. Si se selecciona un aulario origen, este aulario mostrará los menús del aulario seleccionado en lugar de los propios.</p>
-            
             <div class="mb-3">
-                <label for="share_comedor_from" class="form-label">Menú Comedor - Compartir desde:</label>
-                <select id="share_comedor_from" name="share_comedor_from" class="form-select">
-                    <option value="none">No compartir (usar datos propios)</option>
-                    <?php foreach ($available_aularios as $aul_id => $aul_name): ?>
-                        <option value="<?php echo htmlspecialchars($aul_id); ?>" 
-                            <?php echo ($aulario_data['shared_comedor_from'] ?? '') === $aul_id ? 'selected' : ''; ?>>
-                            <?php echo htmlspecialchars($aul_name); ?>
-                        </option>
+                <label for="shared_comedor_from" class="form-label">Compartir comedor de:</label>
+                <select id="shared_comedor_from" name="shared_comedor_from" class="form-select">
+                    <option value="">-- Sin compartir --</option>
+                    <?php foreach ($other_aularios as $aid => $adata): if ($aid === $aulario_id) continue; ?>
+                    <option value="<?= htmlspecialchars($aid) ?>" <?= ($aulario['shared_comedor_from'] ?? '') === $aid ? 'selected' : '' ?>><?= htmlspecialchars($adata['name'] ?? $aid) ?></option>
                     <?php endforeach; ?>
                 </select>
             </div>
-            
-            <hr>
-            <h3>Proyectos Enlazados</h3>
-            <p class="text-muted">Selecciona proyectos raíz específicos de otros aularios para mostrarlos en este aulario. Puedes configurar el nivel de permisos: Solo lectura, Solicitar permiso para cambiar, o Cambiar sin solicitar.</p>
-            
-            <div id="linked-projects-container">
-                <?php
-                $existing_links = $aulario_data['linked_projects'] ?? [];
-                if (count($existing_links) === 0) {
-                    // Show one empty row
-                    $existing_links = [["source_aulario" => "", "project_id" => "", "permission" => "read_only"]];
-                }
-                foreach ($existing_links as $idx => $link):
-                    $source_aul = $link['source_aulario'] ?? '';
-                    $proj_id = $link['project_id'] ?? '';
-                    $permission = $link['permission'] ?? 'read_only';
-                ?>
-                <div class="row mb-2 linked-project-row">
-                    <div class="col-md-4">
-                        <select name="linked_aulario[]" class="form-select linked-aulario-select" data-row="<?php echo $idx; ?>">
-                            <option value="">-- Seleccionar aulario origen --</option>
-                            <?php foreach ($available_aularios as $aul_id => $aul_name): ?>
-                                <option value="<?php echo htmlspecialchars($aul_id); ?>" 
-                                    <?php echo $source_aul === $aul_id ? 'selected' : ''; ?>>
-                                    <?php echo htmlspecialchars($aul_name); ?>
-                                </option>
-                            <?php endforeach; ?>
-                        </select>
-                    </div>
-                    <div class="col-md-3">
-                        <select name="linked_project_id[]" class="form-select linked-project-select" data-row="<?php echo $idx; ?>">
-                            <option value="">-- Seleccionar proyecto --</option>
-                            <?php if (!empty($source_aul) && isset($available_projects_by_aulario[$source_aul])): ?>
-                                <?php foreach ($available_projects_by_aulario[$source_aul] as $proj): ?>
-                                    <option value="<?php echo htmlspecialchars($proj['id']); ?>"
-                                        <?php echo $proj_id === $proj['id'] ? 'selected' : ''; ?>>
-                                        <?php echo htmlspecialchars($proj['name']); ?>
-                                    </option>
-                                <?php endforeach; ?>
-                            <?php endif; ?>
-                        </select>
-                    </div>
-                    <div class="col-md-3">
-                        <select name="linked_permission[]" class="form-select">
-                            <option value="read_only" <?php echo $permission === 'read_only' ? 'selected' : ''; ?>>Solo lectura</option>
-                            <option value="request_edit" <?php echo $permission === 'request_edit' ? 'selected' : ''; ?>>Solicitar permiso para cambiar</option>
-                            <option value="full_edit" <?php echo $permission === 'full_edit' ? 'selected' : ''; ?>>Cambiar sin solicitar</option>
-                        </select>
-                    </div>
-                    <div class="col-md-2">
-                        <button type="button" class="btn btn-danger remove-link-btn" onclick="removeLinkedProject(this)">Eliminar</button>
-                    </div>
-                </div>
-                <?php endforeach; ?>
-            </div>
-            
-            <button type="button" class="btn btn-secondary mb-3" onclick="addLinkedProject()">+ Añadir Proyecto Enlazado</button>
-            
-            <script>
-                // Store available projects data
-                const availableProjects = <?php echo json_encode($available_projects_by_aulario); ?>;
-                let rowCounter = <?php echo count($existing_links); ?>;
-                
-                function addLinkedProject() {
-                    const container = document.getElementById('linked-projects-container');
-                    const newRow = document.createElement('div');
-                    newRow.className = 'row mb-2 linked-project-row';
-                    newRow.innerHTML = `
-                        <div class="col-md-4">
-                            <select name="linked_aulario[]" class="form-select linked-aulario-select" data-row="${rowCounter}">
-                                <option value="">-- Seleccionar aulario origen --</option>
-                                <?php foreach ($available_aularios as $aul_id => $aul_name): ?>
-                                    <option value="<?php echo htmlspecialchars($aul_id); ?>">
-                                        <?php echo htmlspecialchars($aul_name); ?>
-                                    </option>
-                                <?php endforeach; ?>
-                            </select>
-                        </div>
-                        <div class="col-md-3">
-                            <select name="linked_project_id[]" class="form-select linked-project-select" data-row="${rowCounter}">
-                                <option value="">-- Seleccionar proyecto --</option>
-                            </select>
-                        </div>
-                        <div class="col-md-3">
-                            <select name="linked_permission[]" class="form-select">
-                                <option value="read_only">Solo lectura</option>
-                                <option value="request_edit">Solicitar permiso para cambiar</option>
-                                <option value="full_edit">Cambiar sin solicitar</option>
-                            </select>
-                        </div>
-                        <div class="col-md-2">
-                            <button type="button" class="btn btn-danger remove-link-btn" onclick="removeLinkedProject(this)">Eliminar</button>
-                        </div>
-                    `;
-                    container.appendChild(newRow);
-                    
-                    // Attach change event to new aulario select
-                    const newAularioSelect = newRow.querySelector('.linked-aulario-select');
-                    newAularioSelect.addEventListener('change', updateProjectOptions);
-                    
-                    rowCounter++;
-                }
-                
-                function removeLinkedProject(btn) {
-                    btn.closest('.linked-project-row').remove();
-                }
-                
-                function updateProjectOptions(event) {
-                    const aularioSelect = event.target;
-                    const rowId = aularioSelect.dataset.row;
-                    const projectSelect = document.querySelector(`.linked-project-select[data-row="${rowId}"]`);
-                    const selectedAulario = aularioSelect.value;
-                    
-                    // Clear project options
-                    projectSelect.innerHTML = '<option value="">-- Seleccionar proyecto --</option>';
-                    
-                    // Add new options
-                    if (selectedAulario && availableProjects[selectedAulario]) {
-                        availableProjects[selectedAulario].forEach(proj => {
-                            const option = document.createElement('option');
-                            option.value = proj.id;
-                            option.textContent = proj.name;
-                            projectSelect.appendChild(option);
-                        });
-                    }
-                }
-                
-                // Attach event listeners to existing selects
-                document.addEventListener('DOMContentLoaded', function() {
-                    document.querySelectorAll('.linked-aulario-select').forEach(select => {
-                        select.addEventListener('change', updateProjectOptions);
-                    });
-                });
-            </script>
-            
-            <input type="hidden" name="aulario_id" value="<?php echo htmlspecialchars($aulario_id); ?>">
-            <input type="hidden" name="centro_id" value="<?php echo htmlspecialchars($centro_id); ?>">
             <button type="submit" class="btn btn-primary">Guardar Cambios</button>
         </form>
-        <form method="post" action="?form=delete" style="display: inline;">
-            <input type="hidden" name="aulario_id" value="<?php echo htmlspecialchars($aulario_id); ?>">
-            <input type="hidden" name="centro_id" value="<?php echo htmlspecialchars($centro_id); ?>">
-            <button type="submit" class="btn btn-danger" onclick="return confirm('¿Estás seguro de que deseas eliminar este aulario? Esta acción no se puede deshacer.')">Eliminar Aulario</button>
+        <hr>
+        <form method="post" action="?form=delete" onsubmit="return confirm('¿Eliminar este aulario? Se borrarán todos sus datos.')">
+            <input type="hidden" name="aulario_id" value="<?= htmlspecialchars($aulario_id) ?>">
+            <input type="hidden" name="centro_id"  value="<?= htmlspecialchars($centro_id) ?>">
+            <button type="submit" class="btn btn-danger">Eliminar Aulario</button>
         </form>
     </div>
 </div>
-<?php 
+<?php
+        require_once "_incl/post-body.php";
         break;
     case "index":
     default:
+        require_once "_incl/pre-body.php";
+        $all_centros = db_get_centros();
 ?>
 <div class="card pad">
     <div>
-        <h1 class="card-title">Gestión de Aularios</h1>
-        <span>
-            Desde esta sección puedes administrar los aularios asociados al centro que estás administrando.
-        </span>
-        <table class="table table-striped table-hover">
-            <thead class="table-dark">
-                <tr>
-                    <th>Icono</th>
-                    <th>Nombre</th>
-                    <th>
-                        <a href="?action=new" class="btn btn-success">+ Nuevo</a>
-                    </th>
-                </tr>
-            </thead>
-            <tbody>
-                <?php
-                $user_data = $_SESSION["auth_data"];
-                $centro_filter = safe_path_segment(Sf($_GET['centro'] ?? ""));
-                if ($centro_filter !== "") {
-                    $aulas_filelist = glob("/DATA/entreaulas/Centros/$centro_filter/Aularios/*.json") ?: [];
-                } else {
-                    $aulas_filelist = glob("/DATA/entreaulas/Centros/*/Aularios/*.json") ?: [];
-                }
-                foreach ($aulas_filelist as $aula_file) {
-                    $aula_data = json_decode(file_get_contents($aula_file), true);
-                    $centro_id = basename(dirname(dirname($aula_file)));
-                    echo '<tr>';
-                    echo '<td><img src="' . htmlspecialchars($aula_data['icon'] ?? '/static/logo-entreaulas.png') . '" alt="Icono" style="height: 50px;"></td>';
-                    echo '<td>' . htmlspecialchars($aula_data['name'] ?? 'Sin Nombre') . '<br><small>' . $centro_id . '</small></td>';
-                    echo '<td><a href="?action=edit&aulario=' . urlencode(basename($aula_file, ".json")) . '&centro=' . urlencode($centro_id) . '" class="btn btn-primary">Gestionar</a></td>';
-                    echo '</tr>';
-                }
-                ?>
-            </tbody>
-        </table>
+        <h1>Gestión de Aularios</h1>
+        <?php foreach ($all_centros as $c): ?>
+            <?php $aularios = db_get_aularios($c['centro_id']); ?>
+            <h2><?= htmlspecialchars($c['centro_id']) ?></h2>
+            <table class="table table-striped table-hover">
+                <thead class="table-dark">
+                    <tr>
+                        <th>Icono</th><th>Nombre</th>
+                        <th><a href="?action=new&centro=<?= urlencode($c['centro_id']) ?>" class="btn btn-success">+ Nuevo</a></th>
+                    </tr>
+                </thead>
+                <tbody>
+                    <?php foreach ($aularios as $aid => $adata): ?>
+                    <tr>
+                        <td><img src="<?= htmlspecialchars($adata['icon'] ?: '/static/logo-entreaulas.png') ?>" style="height: 50px;"></td>
+                        <td><?= htmlspecialchars($adata['name'] ?: $aid) ?></td>
+                        <td><a href="?action=edit&aulario=<?= urlencode($aid) ?>&centro=<?= urlencode($c['centro_id']) ?>" class="btn btn-primary">Editar</a></td>
+                    </tr>
+                    <?php endforeach; ?>
+                </tbody>
+            </table>
+        <?php endforeach; ?>
     </div>
 </div>
-<?php 
+<?php
+        require_once "_incl/post-body.php";
         break;
 }
-
-
-
-require_once "_incl/post-body.php"; ?>
\ No newline at end of file
diff --git a/public_html/sysadmin/centros.php b/public_html/sysadmin/centros.php
index 5cb06dd..2aa6be5 100644
--- a/public_html/sysadmin/centros.php
+++ b/public_html/sysadmin/centros.php
@@ -1,10 +1,11 @@
 <?php
 require_once "_incl/auth_redir.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 function safe_path_segment($value)
 {
-    $value = trim((string)$value);
+    $value = trim((string) $value);
     $value = str_replace(["\0", "/", "\\"], "", $value);
     $value = str_replace("..", "", $value);
     $value = basename($value);
@@ -21,25 +22,34 @@ switch ($form_action) {
         if (empty($centro_id)) {
             die("Nombre del centro no proporcionado.");
         }
-        $centro_path = "/DATA/entreaulas/Centros/$centro_id";
-        if (is_dir($centro_path)) {
+        // Check uniqueness in DB
+        $existing = db()->prepare("SELECT id FROM centros WHERE centro_id = ?");
+        $existing->execute([$centro_id]);
+        if ($existing->fetch()) {
             die("El centro ya existe.");
         }
-        mkdir($centro_path, 0777, true);
+        // Create DB record
+        db()->prepare("INSERT INTO centros (centro_id) VALUES (?)")->execute([$centro_id]);
+        // Keep filesystem directory for activity photos (Panel/Actividades)
+        $centro_path = "/DATA/entreaulas/Centros/$centro_id";
+        if (!is_dir($centro_path)) {
+            mkdir($centro_path, 0755, true);
+        }
         header("Location: ?action=index");
         exit();
         break;
     case "create_activity":
         ini_set('memory_limit', '512M');
-        ini_set("display_errors", 1);
         ini_set('upload_max_filesize', '256M');
         ini_set('post_max_size', '256M');
         $centro_id = safe_path_segment(Sf($_GET['centro'] ?? ''));
-        $centro_path = "/DATA/entreaulas/Centros/$centro_id";
-        if (!is_dir($centro_path)) {
+        // Validate centro exists in DB
+        $stmt = db()->prepare("SELECT id FROM centros WHERE centro_id = ?");
+        $stmt->execute([$centro_id]);
+        if (!$stmt->fetch()) {
             die("Centro no válido.");
         }
-        $activity_name = safe_path_segment(Sf($_POST["name"] ?? ''));
+        $activity_name  = safe_path_segment(Sf($_POST["name"] ?? ''));
         if (empty($activity_name)) {
             die("Nombre de la actividad no proporcionado.");
         }
@@ -47,22 +57,20 @@ switch ($form_action) {
         if ($activity_photo === null || $activity_photo["error"] !== UPLOAD_ERR_OK) {
             die("Error al subir la foto.");
         }
-        $activity_path = "$centro_path/Panel/Actividades/$activity_name";
+        $activity_path = "/DATA/entreaulas/Centros/$centro_id/Panel/Actividades/$activity_name";
         if (is_dir($activity_path)) {
             die("La actividad ya existe.");
         }
-        mkdir($activity_path, 0777, true);
-        $photo_path = "$activity_path/photo.jpg";
-        move_uploaded_file($activity_photo["tmp_name"], $photo_path);
+        mkdir($activity_path, 0755, true);
+        move_uploaded_file($activity_photo["tmp_name"], "$activity_path/photo.jpg");
         header("Location: ?action=edit&centro=" . urlencode($centro_id));
         exit();
         break;
     case "edit_activity":
         ini_set('memory_limit', '512M');
-        ini_set("display_errors", 1);
         ini_set('upload_max_filesize', '256M');
         ini_set('post_max_size', '256M');
-        $centro_id = safe_path_segment(Sf($_GET['centro'] ?? ''));
+        $centro_id     = safe_path_segment(Sf($_GET['centro'] ?? ''));
         $activity_name = safe_path_segment(Sf($_GET['activity'] ?? ''));
         $activity_path = "/DATA/entreaulas/Centros/$centro_id/Panel/Actividades/$activity_name";
         if (!is_dir($activity_path)) {
@@ -70,27 +78,26 @@ switch ($form_action) {
         }
         $activity_photo = $_FILES["file"] ?? null;
         if ($activity_photo !== null && $activity_photo["error"] === UPLOAD_ERR_OK) {
-            $photo_path = "$activity_path/photo.jpg";
-            move_uploaded_file($activity_photo["tmp_name"], $photo_path);
+            move_uploaded_file($activity_photo["tmp_name"], "$activity_path/photo.jpg");
         }
-        if (safe_path_segment(Sf($_POST['nombre'] ?? '')) != $activity_name) {
-            $new_activity_name = safe_path_segment(Sf($_POST['nombre'] ?? ''));
-            $new_activity_path = "/DATA/entreaulas/Centros/$centro_id/Panel/Actividades/$new_activity_name";
-            if (is_dir($new_activity_path)) {
+        $new_name = safe_path_segment(Sf($_POST['nombre'] ?? ''));
+        if ($new_name !== $activity_name && $new_name !== '') {
+            $new_path = "/DATA/entreaulas/Centros/$centro_id/Panel/Actividades/$new_name";
+            if (is_dir($new_path)) {
                 die("Ya existe una actividad con ese nombre.");
             }
-            rename($activity_path, $new_activity_path);
+            rename($activity_path, $new_path);
         }
-        header("Location: ?action=edit&centro=" . urlencode($centro_id));;
+        header("Location: ?action=edit&centro=" . urlencode($centro_id));
         exit();
         break;
 }
 
-require_once "_incl/pre-body.php"; 
+require_once "_incl/pre-body.php";
 $view_action = $_GET["action"] ?? "index";
 switch ($view_action) {
     case "edit_activity":
-        $centro_id = safe_path_segment(Sf($_GET['centro'] ?? ''));
+        $centro_id     = safe_path_segment(Sf($_GET['centro'] ?? ''));
         $activity_name = safe_path_segment(Sf($_GET['activity'] ?? ''));
         $activity_path = "/DATA/entreaulas/Centros/$centro_id/Panel/Actividades/$activity_name";
         if (!is_dir($activity_path)) {
@@ -99,22 +106,20 @@ switch ($view_action) {
 ?>
 <div class="card pad">
     <div>
-        <h1 class="card-title">Gestión de la Actividad: <?php echo htmlspecialchars($activity_name); ?></h1>
-        <span>
-            Desde esta sección puedes administrar la actividad seleccionada del panel del centro <?php echo htmlspecialchars($centro_id); ?>.
-        </span>
-        <form method="post" action="?form=edit_activity&centro=<?php echo urlencode($centro_id); ?>&activity=<?php echo urlencode($activity_name); ?>" enctype="multipart/form-data">
+        <h1 class="card-title">Gestión de la Actividad: <?= htmlspecialchars($activity_name) ?></h1>
+        <form method="post" action="?form=edit_activity&centro=<?= urlencode($centro_id) ?>&activity=<?= urlencode($activity_name) ?>" enctype="multipart/form-data">
             <div class="mb-3">
                 <label for="nombre" class="form-label">Nombre de la actividad:</label>
-                <input required type="text" id="nombre" name="nombre" class="form-control" value="<?php echo htmlspecialchars($activity_name); ?>">
+                <input required type="text" id="nombre" name="nombre" class="form-control" value="<?= htmlspecialchars($activity_name) ?>">
             </div>
             <div class="mb-3">
                 <label class="form-label">Foto (pulsa para cambiarla):</label><br>
                 <div style="width: 200px;">
                     <label class="dropimage" style="background-image: url('<?php
-                        $image_path = "$activity_path/photo.jpg";
-                        $image_fetchpath = file_exists($image_path) ? "/entreaulas/_filefetch.php?type=panel_actividades&centro=" . urlencode($centro_id) . "&activity=" . urlencode($activity_name) : '/static/logo-entreaulas.png';
-                        echo htmlspecialchars($image_fetchpath);
+                        $img = file_exists("$activity_path/photo.jpg")
+                            ? "/entreaulas/_filefetch.php?type=panel_actividades&centro=" . urlencode($centro_id) . "&activity=" . urlencode($activity_name)
+                            : '/static/logo-entreaulas.png';
+                        echo htmlspecialchars($img);
                     ?>');">
                         <input title="Drop image or click me" type="file" name="file" accept="image/*">
                     </label>
@@ -128,18 +133,16 @@ switch ($view_action) {
         break;
     case "new_activity":
         $centro_id = safe_path_segment(Sf($_GET['centro'] ?? ''));
-        $centro_path = "/DATA/entreaulas/Centros/$centro_id";
-        if (!is_dir($centro_path)) {
+        $stmt = db()->prepare("SELECT id FROM centros WHERE centro_id = ?");
+        $stmt->execute([$centro_id]);
+        if (!$stmt->fetch()) {
             die("Centro no válido.");
         }
 ?>
 <div class="card pad">
     <div>
         <h1 class="card-title">Nueva Actividad del Panel</h1>
-        <span>
-            Aquí puedes crear una nueva actividad para el panel del centro <?php echo htmlspecialchars($centro_id); ?>.
-        </span>
-        <form method="post" action="?form=create_activity&centro=<?php echo urlencode($centro_id); ?>" enctype="multipart/form-data">
+        <form method="post" action="?form=create_activity&centro=<?= urlencode($centro_id) ?>" enctype="multipart/form-data">
             <div class="mb-3">
                 <label for="name" class="form-label">Nombre de la actividad:</label>
                 <input required type="text" id="name" name="name" class="form-control" placeholder="Ej: Biblioteca">
@@ -155,13 +158,10 @@ switch ($view_action) {
 <?php
         break;
     case "new":
-        ?>
+?>
 <div class="card pad">
     <div>
         <h1 class="card-title">Nuevo Centro</h1>
-        <span>
-            Aquí puedes crear un nuevo centro para el sistema.
-        </span>
         <form method="post" action="?form=create">
             <div class="mb-3">
                 <label for="name" class="form-label">ID del centro:</label>
@@ -171,22 +171,21 @@ switch ($view_action) {
         </form>
     </div>
 </div>
-
 <?php
         break;
     case "edit":
         $centro_id = safe_path_segment(Sf($_GET['centro'] ?? ''));
-        $centro_path = "/DATA/entreaulas/Centros/$centro_id";
-        if (!is_dir($centro_path)) {
+        $stmt = db()->prepare("SELECT id FROM centros WHERE centro_id = ?");
+        $stmt->execute([$centro_id]);
+        if (!$stmt->fetch()) {
             die("Centro no válido.");
         }
+        $aularios   = db_get_aularios($centro_id);
+        $activities = glob("/DATA/entreaulas/Centros/$centro_id/Panel/Actividades/*", GLOB_ONLYDIR) ?: [];
 ?>
 <div class="card pad">
     <div>
-        <h1 class="card-title">Gestión del Centro: <?php echo htmlspecialchars($centro_id); ?></h1>
-        <span>
-            Desde esta sección puedes administrar el centro seleccionado.
-        </span>
+        <h1 class="card-title">Gestión del Centro: <?= htmlspecialchars($centro_id) ?></h1>
     </div>
 </div>
 <div class="card pad">
@@ -195,25 +194,18 @@ switch ($view_action) {
         <table class="table table-striped table-hover">
             <thead class="table-dark">
                 <tr>
-                    <th>Icono</th>
-                    <th>Nombre</th>
-                    <th>
-                        <a href="/sysadmin/aularios.php?action=new&centro=<?php echo urlencode($centro_id); ?>" class="btn btn-success">+ Nuevo</a>
-                    </th>
+                    <th>Icono</th><th>Nombre</th>
+                    <th><a href="/sysadmin/aularios.php?action=new&centro=<?= urlencode($centro_id) ?>" class="btn btn-success">+ Nuevo</a></th>
                 </tr>
             </thead>
             <tbody>
-                <?php
-                $aulas_filelist = glob("/DATA/entreaulas/Centros/$centro_id/Aularios/*.json");
-                foreach ($aulas_filelist as $aula_file) {
-                    $aula_data = json_decode(file_get_contents($aula_file), true);
-                    echo '<tr>';
-                    echo '<td><img src="' . htmlspecialchars($aula_data['icon'] ?? '/static/logo-entreaulas.png') . '" alt="Icono" style="height: 50px;"></td>';
-                    echo '<td>' . htmlspecialchars($aula_data['name'] ?? 'Sin Nombre') . '</td>';
-                    echo '<td><a href="/sysadmin/aularios.php?action=edit&aulario=' . urlencode(basename($aula_file, ".json")) . '&centro=' . urlencode($centro_id) . '" class="btn btn-primary">Gestionar</a></td>';
-                    echo '</tr>';
-                }
-                ?>
+                <?php foreach ($aularios as $aula_id => $aula): ?>
+                <tr>
+                    <td><img src="<?= htmlspecialchars($aula['icon'] ?: '/static/logo-entreaulas.png') ?>" alt="Icono" style="height: 50px;"></td>
+                    <td><?= htmlspecialchars($aula['name'] ?: $aula_id) ?></td>
+                    <td><a href="/sysadmin/aularios.php?action=edit&aulario=<?= urlencode($aula_id) ?>&centro=<?= urlencode($centro_id) ?>" class="btn btn-primary">Gestionar</a></td>
+                </tr>
+                <?php endforeach; ?>
             </tbody>
         </table>
     </div>
@@ -224,70 +216,52 @@ switch ($view_action) {
         <table class="table table-striped table-hover">
             <thead class="table-dark">
                 <tr>
-                    <th>Foto</th>
-                    <th>Nombre</th>
-                    <th>
-                        <a href="?action=new_activity&centro=<?php echo urlencode($centro_id); ?>" class="btn btn-success">+ Nuevo</a>
-                    </th>
+                    <th>Foto</th><th>Nombre</th>
+                    <th><a href="?action=new_activity&centro=<?= urlencode($centro_id) ?>" class="btn btn-success">+ Nuevo</a></th>
                 </tr>
             </thead>
             <tbody>
-                <?php
-                $activities = glob("/DATA/entreaulas/Centros/$centro_id/Panel/Actividades/*", GLOB_ONLYDIR);
-                foreach ($activities as $activity_path) {
-                    $activity_name = basename($activity_path);
-                    $image_path = "/DATA/entreaulas/Centros/$centro_id/Panel/Actividades/" . basename($activity_name) . "/photo.jpg";
-                    $image_fetchpath = file_exists($image_path) ? "/entreaulas/_filefetch.php?type=panel_actividades&centro=" . urlencode($centro_id) . "&activity=" . urlencode($activity_name) : '/static/logo-entreaulas.png';
-                    echo '<tr>';
-                    echo '<td><img src="' . htmlspecialchars($image_fetchpath) . '" alt="Foto" style="height: 50px;"></td>';
-                    echo '<td>' . htmlspecialchars($activity_name) . '</td>';
-                    echo '<td><a href="?action=edit_activity&centro=' . urlencode($centro_id) . '&activity=' . urlencode($activity_name) . '" class="btn btn-primary">Gestionar</a></td>';
-                    echo '</tr>';
-                }
-                ?>
+                <?php foreach ($activities as $ap): ?>
+                <?php $an = basename($ap); $img_path = "$ap/photo.jpg"; ?>
+                <tr>
+                    <td><img src="<?= file_exists($img_path) ? htmlspecialchars("/entreaulas/_filefetch.php?type=panel_actividades&centro=" . urlencode($centro_id) . "&activity=" . urlencode($an)) : '/static/logo-entreaulas.png' ?>" style="height: 50px;"></td>
+                    <td><?= htmlspecialchars($an) ?></td>
+                    <td><a href="?action=edit_activity&centro=<?= urlencode($centro_id) ?>&activity=<?= urlencode($an) ?>" class="btn btn-primary">Gestionar</a></td>
+                </tr>
+                <?php endforeach; ?>
             </tbody>
         </table>
     </div>
 </div>
-
-    <?php
+<?php
         break;
     case "index":
     default:
+        $all_centros = db_get_centros();
 ?>
 <div class="card pad">
     <div>
         <h1 class="card-title">Gestión de Centros</h1>
-        <span>
-            Desde esta sección puedes administrar los centros asociados al sistema.
-        </span>
         <table class="table table-striped table-hover">
             <thead class="table-dark">
                 <tr>
-                    <th>Nombre</th>
-                    <th>
-                        <a href="?action=new" class="btn btn-success">+ Nuevo</a>
-                    </th>
+                    <th>Centro</th>
+                    <th><a href="?action=new" class="btn btn-success">+ Nuevo</a></th>
                 </tr>
             </thead>
             <tbody>
-                <?php
-                $user_data = $_SESSION["auth_data"];
-                $centros_filelist = glob("/DATA/entreaulas/Centros/*");
-                foreach ($centros_filelist as $centro_folder) {
-                    $centro_id = basename($centro_folder);
-                    echo '<tr>';
-                    echo '<td>' . htmlspecialchars($centro_id) . '</td>';
-                    echo '<td><a href="?action=edit&centro=' . urlencode($centro_id) . '" class="btn btn-primary">Gestionar</a></td>';
-                    echo '</tr>';
-                }
-                ?>
+                <?php foreach ($all_centros as $c): ?>
+                <tr>
+                    <td><?= htmlspecialchars($c['centro_id']) ?></td>
+                    <td><a href="?action=edit&centro=<?= urlencode($c['centro_id']) ?>" class="btn btn-primary">Gestionar</a></td>
+                </tr>
+                <?php endforeach; ?>
             </tbody>
         </table>
     </div>
 </div>
-<?php 
+<?php
         break;
 }
 
-require_once "_incl/post-body.php"; ?>
\ No newline at end of file
+require_once "_incl/post-body.php";
diff --git a/public_html/sysadmin/invitations.php b/public_html/sysadmin/invitations.php
index 2364f2e..50b1af6 100644
--- a/public_html/sysadmin/invitations.php
+++ b/public_html/sysadmin/invitations.php
@@ -1,100 +1,91 @@
 <?php
 require_once "_incl/auth_redir.php";
+require_once "../_incl/db.php";
 
-switch ($_GET['form']) {
+switch ($_GET['form'] ?? '') {
     case "create":
-        // Handle creation logic here
-        $invitations = json_decode(file_get_contents("/DATA/Invitaciones_de_usuarios.json"), true) ?? [];
-        $invitation_code = strtoupper($_POST['invitation_code'] ?? '');
-        $single_use = isset($_POST['single_use']) ? true : false;
-        if (isset($invitations[$invitation_code])) {
+        $code       = strtoupper(trim($_POST['invitation_code'] ?? ''));
+        $single_use = isset($_POST['single_use']);
+        if (empty($code)) {
+            header("Location: /sysadmin/invitations.php?action=new&_resultcolor=red&_result=" . urlencode("Código de invitación vacío."));
+            exit;
+        }
+        if (db_get_invitation($code)) {
             header("Location: /sysadmin/invitations.php?action=new&_resultcolor=red&_result=" . urlencode("El código de invitación ya existe."));
             exit;
         }
-        $invitations[$invitation_code] = [
-            "active" => true,
-            "single_use" => $single_use
-        ];
-        file_put_contents("/DATA/Invitaciones_de_usuarios.json", json_encode($invitations, JSON_PRETTY_PRINT));
-        header("Location: /sysadmin/invitations.php?_result=" . urlencode("Código $invitation_code creado correctamente."));
+        db_upsert_invitation($code, true, $single_use);
+        header("Location: /sysadmin/invitations.php?_result=" . urlencode("Código $code creado correctamente."));
         exit;
         break;
     case "delete":
-        // Handle deletion logic here
-        $invitations = json_decode(file_get_contents("/DATA/Invitaciones_de_usuarios.json"), true) ?? [];
-        $invitation_code = strtoupper($_POST['invitation_code'] ?? '');
-        if (isset($invitations[$invitation_code])) {
-            unset($invitations[$invitation_code]);
-            file_put_contents("/DATA/Invitaciones_de_usuarios.json", json_encode($invitations, JSON_PRETTY_PRINT));
-        }
-        header("Location: /sysadmin/invitations.php?_result=" . urlencode("Codigo $invitation_code borrado"));
+        $code = strtoupper(trim($_POST['invitation_code'] ?? ''));
+        db_delete_invitation($code);
+        header("Location: /sysadmin/invitations.php?_result=" . urlencode("Código $code borrado."));
         exit;
         break;
 }
 
 require_once "_incl/pre-body.php";
-switch ($_GET['action']) {
+switch ($_GET['action'] ?? 'index') {
     case "new":
-        ?>
-        <div class="card pad">
-            <div>
-                <h1 class="card-title">Nueva invitación de usuario</h1>
-                <form method="post" action="?form=create">
-                    <div class="card pad" style="max-width: 500px;">
-                        <div>
-                            <div class="mb-3">
-                                <label for="invitation_code" class="form-label"><b>Código de invitación:</b></label>
-                                <input type="text" id="invitation_code" name="invitation_code" class="form-control" required />
-                                <small>Formato: 123456-ABCDEF</small>
-                            </div>
-                            <div class="form-check mb-3">
-                                <input class="form-check-input" type="checkbox" name="single_use" id="single_use">
-                                <label class="form-check-label" for="single_use">
-                                    Uso único
-                                </label>
-                            </div>
-                            <button type="submit" class="btn btn-primary">Crear invitación</button>
-                        </div>
+?>
+<div class="card pad">
+    <div>
+        <h1 class="card-title">Nueva invitación de usuario</h1>
+        <form method="post" action="?form=create">
+            <div class="card pad" style="max-width: 500px;">
+                <div>
+                    <div class="mb-3">
+                        <label for="invitation_code" class="form-label"><b>Código de invitación:</b></label>
+                        <input type="text" id="invitation_code" name="invitation_code" class="form-control" required />
+                        <small>Formato: 123456-ABCDEF</small>
                     </div>
-                </form>
+                    <div class="form-check mb-3">
+                        <input class="form-check-input" type="checkbox" name="single_use" id="single_use">
+                        <label class="form-check-label" for="single_use">Uso único</label>
+                    </div>
+                    <button type="submit" class="btn btn-primary">Crear invitación</button>
+                </div>
             </div>
-        </div>
-        <?php
+        </form>
+    </div>
+</div>
+<?php
         break;
     default:
     case "index":
-        ?>
-        <div class="card pad">
-            <div>
-                <h1>Invitaciones de usuarios</h1>
-                <span>Desde aquí puedes gestionar las invitaciones de usuarios.</span>
-                <table class="table table-striped table-hover">
-                    <thead class="table-dark">
-                        <th>Codigo de invitación</th>
-                        <th>
-                            <a href="?action=new" class="btn btn-success">+ Nuevo</a>
-                        </th>
-                    </thead>
-                    <tbody>
-                        <?php
-                        $invitations = json_decode(file_get_contents("/DATA/Invitaciones_de_usuarios.json"), true);
-                        foreach ($invitations as $inv_key => $inv_data) {
-                            echo "<tr>";
-                            echo "<td>" . htmlspecialchars($inv_key) . "</td>";
-                            echo "<td>";
-                            echo '<form method="post" action="?form=delete" style="display:inline;">';
-                            echo '<input type="hidden" name="invitation_code" value="' . htmlspecialchars($inv_key) . '"/>';
-                            echo '<button type="submit" class="btn btn-danger" onclick="return confirm(\'¿Estás seguro de que deseas eliminar esta invitación?\');">Eliminar</button>';
-                            echo '</form>';
-                            echo "</td>";
-                            echo "</tr>";
-                        }
-                        ?>
-                    </tbody>
-                </table>
-            </div>
-        </div>
+        $invitations = db_get_all_invitations();
+?>
+<div class="card pad">
+    <div>
+        <h1>Invitaciones de usuarios</h1>
+        <table class="table table-striped table-hover">
+            <thead class="table-dark">
+                <th>Código</th>
+                <th>Activo</th>
+                <th>Uso único</th>
+                <th><a href="?action=new" class="btn btn-success">+ Nuevo</a></th>
+            </thead>
+            <tbody>
+                <?php foreach ($invitations as $inv): ?>
+                <tr>
+                    <td><?= htmlspecialchars($inv['code']) ?></td>
+                    <td><?= $inv['active'] ? 'Sí' : 'No' ?></td>
+                    <td><?= $inv['single_use'] ? 'Sí' : 'No' ?></td>
+                    <td>
+                        <form method="post" action="?form=delete" style="display:inline">
+                            <input type="hidden" name="invitation_code" value="<?= htmlspecialchars($inv['code']) ?>">
+                            <button type="submit" class="btn btn-danger btn-sm">Borrar</button>
+                        </form>
+                    </td>
+                </tr>
+                <?php endforeach; ?>
+            </tbody>
+        </table>
+    </div>
+</div>
 <?php
         break;
 }
-require_once "_incl/post-body.php";
\ No newline at end of file
+require_once "_incl/post-body.php";
diff --git a/public_html/sysadmin/reset_password.php b/public_html/sysadmin/reset_password.php
index 8453334..2b5de57 100644
--- a/public_html/sysadmin/reset_password.php
+++ b/public_html/sysadmin/reset_password.php
@@ -1,93 +1,75 @@
 <?php
 require_once "_incl/auth_redir.php";
-require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 function safe_username($value)
 {
-  $value = basename((string)$value);
-  $value = preg_replace('/[^a-zA-Z0-9._-]/', '', $value);
-  if (strpos($value, '..') !== false) {
-    return '';
-  }
-  return $value;
+    $value = strtolower(basename((string) $value));
+    $value = preg_replace('/[^a-zA-Z0-9._@-]/', '', $value);
+    if (strpos($value, '..') !== false) {
+        return '';
+    }
+    return $value;
 }
 
 switch ($_GET['form'] ?? '') {
-  case 'save_password':
-    $username = safe_username($_POST['username'] ?? '');
-    $new_password = $_POST['new_password'] ?? '';
-    $confirm_password = $_POST['confirm_password'] ?? '';
+    case 'save_password':
+        $username         = safe_username($_POST['username'] ?? '');
+        $new_password     = $_POST['new_password'] ?? '';
+        $confirm_password = $_POST['confirm_password'] ?? '';
 
-    if (empty($username)) {
-      die("Nombre de usuario no proporcionado.");
-    }
+        if (empty($username)) {
+            die("Nombre de usuario no proporcionado.");
+        }
+        if (empty($new_password)) {
+            die("La contraseña no puede estar vacía.");
+        }
+        if ($new_password !== $confirm_password) {
+            die("Las contraseñas no coinciden.");
+        }
+        if (strlen($new_password) < 6) {
+            die("La contraseña debe tener al menos 6 caracteres.");
+        }
+        $row = db_get_user($username);
+        if (!$row) {
+            die("Usuario no encontrado.");
+        }
+        db()->prepare("UPDATE users SET password_hash = ?, updated_at = datetime('now') WHERE id = ?")
+            ->execute([password_hash($new_password, PASSWORD_DEFAULT), $row['id']]);
 
-    if (empty($new_password)) {
-      die("La contraseña no puede estar vacía.");
-    }
-
-    if ($new_password !== $confirm_password) {
-      die("Las contraseñas no coinciden.");
-    }
-
-    if (strlen($new_password) < 6) {
-      die("La contraseña debe tener al menos 6 caracteres.");
-    }
-
-    $userfile = "/DATA/Usuarios/$username.json";
-    if (!file_exists($userfile)) {
-      die("Usuario no encontrado.");
-    }
-
-    $userdata = json_decode(file_get_contents($userfile), true);
-    $userdata['password_hash'] = password_hash($new_password, PASSWORD_DEFAULT);
-    
-    file_put_contents($userfile, json_encode($userdata, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
-    
-    header("Location: users.php?action=edit&user=" . urlencode($username) . "&_result=" . urlencode("Contraseña restablecida correctamente a las " . date("H:i:s") . " (hora servidor)."));
-    exit;
-    break;
+        header("Location: users.php?action=edit&user=" . urlencode($username) . "&_result=" . urlencode("Contraseña restablecida correctamente a las " . date("H:i:s") . " (hora servidor)."));
+        exit;
+        break;
 }
 
 require_once "_incl/pre-body.php";
-
 $username = safe_username($_GET['user'] ?? '');
 if (empty($username)) {
-  die("Usuario no especificado.");
+    die("Usuario no especificado.");
 }
-
-$userfile = "/DATA/Usuarios/$username.json";
-if (!file_exists($userfile)) {
-  die("Usuario no encontrado.");
+$row = db_get_user($username);
+if (!$row) {
+    die("Usuario no encontrado.");
 }
-
-$userdata = json_decode(file_get_contents($userfile), true);
 ?>
-
 <form method="post" action="?form=save_password">
   <div class="card pad">
     <div>
-      <h1>Restablecer Contraseña: <?php echo htmlspecialchars($username); ?></h1>
-      
+      <h1>Restablecer Contraseña: <?= htmlspecialchars($username) ?></h1>
       <div class="mb-3">
         <label for="new_password" class="form-label">Nueva Contraseña:</label>
         <input type="password" id="new_password" name="new_password" class="form-control" required minlength="6">
         <small class="form-text text-muted">Mínimo 6 caracteres</small>
       </div>
-      
       <div class="mb-3">
         <label for="confirm_password" class="form-label">Confirmar Contraseña:</label>
         <input type="password" id="confirm_password" name="confirm_password" class="form-control" required minlength="6">
       </div>
-      
-      <input type="hidden" name="username" value="<?php echo htmlspecialchars($username); ?>">
-      
+      <input type="hidden" name="username" value="<?= htmlspecialchars($username) ?>">
       <button type="submit" class="btn btn-primary">Restablecer Contraseña</button>
-      <a href="users.php?action=edit&user=<?php echo urlencode($username); ?>" class="btn btn-secondary">Cancelar</a>
+      <a href="users.php?action=edit&user=<?= urlencode($username) ?>" class="btn btn-secondary">Cancelar</a>
     </div>
   </div>
 </form>
-
 <?php
 require_once "_incl/post-body.php";
-?>
diff --git a/public_html/sysadmin/users.php b/public_html/sysadmin/users.php
index 5ab2696..3aa49e5 100644
--- a/public_html/sysadmin/users.php
+++ b/public_html/sysadmin/users.php
@@ -1,89 +1,54 @@
 <?php
 require_once "_incl/auth_redir.php";
 require_once "../_incl/tools.security.php";
+require_once "../_incl/db.php";
 
 function safe_username($value)
 {
-  $value = basename((string)$value);
-  $value = preg_replace('/[^a-zA-Z0-9._-]/', '', $value);
-  if (strpos($value, '..') !== false) {
-    return '';
-  }
-  return $value;
+    $value = strtolower(basename((string) $value));
+    $value = preg_replace('/[^a-zA-Z0-9._@-]/', '', $value);
+    if (strpos($value, '..') !== false) {
+        return '';
+    }
+    return $value;
 }
 
-define('USERS_DIR', '/DATA/Usuarios/');
-
 switch ($_GET['form'] ?? '') {
-  case 'save_edit':
-    $username = safe_username($_POST['username'] ?? '');
-    if (empty($username)) {
-      die("Nombre de usuario no proporcionado.");
-    }
-    $user_file = get_user_file_path($username);
-    $userdata_old = [];
-    if (is_readable($user_file)) {
-      $file_contents = file_get_contents($user_file);
-      if ($file_contents !== false) {
-        $decoded = json_decode($file_contents, true);
-        if (is_array($decoded)) {
-          $userdata_old = $decoded;
+    case 'save_edit':
+        $username = safe_username($_POST['username'] ?? '');
+        if (empty($username)) {
+            die("Nombre de usuario no proporcionado.");
         }
-      }
-    }
-    $permissions = $_POST['permissions'] ?? [];
-    if (!is_array($permissions)) {
-      $permissions = [];
-    }
+        $permissions = $_POST['permissions'] ?? [];
+        if (!is_array($permissions)) {
+            $permissions = [];
+        }
+        $aulas = $_POST['aulas'] ?? [];
+        if (!is_array($aulas)) {
+            $aulas = [];
+        }
+        $aulas = array_values(array_filter(array_map('safe_aulario_id', $aulas)));
 
-    $aulas = $_POST['aulas'] ?? [];
-    if (!is_array($aulas)) {
-      $aulas = [];
-    }
-    $aulas = array_values(array_filter(array_map('safe_aulario_id', $aulas)));
-
-    $userdata_new = [
-      'display_name' => $_POST['display_name'] ?? '',
-      'email' => $_POST['email'] ?? '',
-      'permissions' => $permissions,
-      'entreaulas' => [
-        'centro' => safe_centro_id($_POST['centro'] ?? ''),
-        'role' => $_POST['role'] ?? '',
-        'aulas' => $aulas
-      ]
-    ];
-    // Merge old and new data to preserve any other fields, like password hashes or custom metadata.
-    $userdata = array_merge($userdata_old, $userdata_new);
-    $user_dir = rtrim(USERS_DIR, '/');
-    $user_file = get_user_file_path($username);
-    if (!is_dir($user_dir) || !is_writable($user_dir)) {
-      die("No se puede guardar el usuario: directorio de datos no disponible.");
-    }
-    $json_data = json_encode($userdata, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE);
-    if ($json_data === false) {
-      die("No se puede guardar el usuario: error al codificar los datos.");
-    }
-    $tmp_file = tempnam($user_dir, 'user_');
-    if ($tmp_file === false) {
-      die("No se puede guardar el usuario: no se pudo crear un archivo temporal.");
-    }
-    $bytes_written = file_put_contents($tmp_file, $json_data, LOCK_EX);
-    if ($bytes_written === false) {
-      @unlink($tmp_file);
-      die("No se puede guardar el usuario: error al escribir en el disco.");
-    }
-    if (!rename($tmp_file, $user_file)) {
-      @unlink($tmp_file);
-      die("No se puede guardar el usuario: no se pudo finalizar la grabación del archivo.");
-    }
-    header("Location: ?action=edit&user=" . urlencode($username) . "&_result=" . urlencode("Cambios guardados correctamente a las ".date("H:i:s")." (hora servidor)."));
-    exit;
-    break;
+        db_upsert_user([
+            'username'     => $username,
+            'display_name' => $_POST['display_name'] ?? '',
+            'email'        => $_POST['email'] ?? '',
+            'permissions'  => $permissions,
+            'entreaulas'   => [
+                'centro' => safe_centro_id($_POST['centro'] ?? ''),
+                'role'   => $_POST['role'] ?? '',
+                'aulas'  => $aulas,
+            ],
+        ]);
+        header("Location: ?action=edit&user=" . urlencode($username) . "&_result=" . urlencode("Cambios guardados correctamente a las " . date("H:i:s") . " (hora servidor)."));
+        exit;
+        break;
 }
 
 switch ($_GET['action'] ?? '') {
-  case 'add':
-    require_once "_incl/pre-body.php";
+    case 'add':
+        require_once "_incl/pre-body.php";
+        $all_centros = db_get_centro_ids();
 ?>
 <form method="post" action="?form=save_edit">
   <div class="card pad">
@@ -104,70 +69,52 @@ switch ($_GET['action'] ?? '') {
       <b>Permisos:</b>
       <div class="accordion mt-3" id="permissionsAccordion">
         <div class="accordion-item">
-          <h2 class="accordion-header" id="headingSysadmin">
-            <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSysadmin" aria-expanded="true" aria-controls="collapseSysadmin">
-              Administración del sistema
-            </button>
+          <h2 class="accordion-header">
+            <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSysadmin">Administración del sistema</button>
           </h2>
-          <div id="collapseSysadmin" class="accordion-collapse collapse show" aria-labelledby="headingSysadmin" data-bs-parent="#permissionsAccordion">
+          <div id="collapseSysadmin" class="accordion-collapse collapse show" data-bs-parent="#permissionsAccordion">
             <div class="accordion-body">
               <div class="form-check">
                 <input class="form-check-input" type="checkbox" name="permissions[]" value="sysadmin:access" id="sysadmin-access">
-                <label class="form-check-label" for="sysadmin-access">
-                  Acceso
-                </label>
+                <label class="form-check-label" for="sysadmin-access">Acceso</label>
               </div>
             </div>
           </div>
         </div>
         <div class="accordion-item">
-          <h2 class="accordion-header" id="headingEntreaulas">
-            <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseEntreaulas" aria-expanded="false" aria-controls="collapseEntreaulas">
-              EntreAulas
-            </button>
+          <h2 class="accordion-header">
+            <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseEntreaulas">EntreAulas</button>
           </h2>
-          <div id="collapseEntreaulas" class="accordion-collapse collapse" aria-labelledby="headingEntreaulas" data-bs-parent="#permissionsAccordion">
+          <div id="collapseEntreaulas" class="accordion-collapse collapse" data-bs-parent="#permissionsAccordion">
             <div class="accordion-body">
               <div class="form-check">
                 <input class="form-check-input" type="checkbox" name="permissions[]" value="entreaulas:access" id="entreaulas-access">
-                <label class="form-check-label" for="entreaulas-access">
-                  Acceso
-                </label>
+                <label class="form-check-label" for="entreaulas-access">Acceso</label>
               </div>
               <div class="form-check">
                 <input class="form-check-input" type="checkbox" name="permissions[]" value="entreaulas:docente" id="entreaulas-docente">
-                <label class="form-check-label" for="entreaulas-docente">
-                  Docente
-                </label>
+                <label class="form-check-label" for="entreaulas-docente">Docente</label>
               </div>
               <div class="form-check">
                 <input class="form-check-input" type="checkbox" name="permissions[]" value="entreaulas:proyectos:delete" id="entreaulas-proyectos-delete">
-                <label class="form-check-label" for="entreaulas-proyectos-delete">
-                  Eliminar Proyectos
-                </label>
+                <label class="form-check-label" for="entreaulas-proyectos-delete">Eliminar Proyectos</label>
               </div>
             </div>
           </div>
         </div>
         <div class="accordion-item">
-          <h2 class="accordion-header" id="headingSupercafe">
-            <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSupercafe" aria-expanded="false" aria-controls="collapseSupercafe">
-              SuperCafe
-            </button>
+          <h2 class="accordion-header">
+            <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSupercafe">SuperCafe</button>
           </h2>
-          <div id="collapseSupercafe" class="accordion-collapse collapse" aria-labelledby="headingSupercafe" data-bs-parent="#permissionsAccordion">
+          <div id="collapseSupercafe" class="accordion-collapse collapse" data-bs-parent="#permissionsAccordion">
             <div class="accordion-body">
               <div class="form-check">
                 <input class="form-check-input" type="checkbox" name="permissions[]" value="supercafe:access" id="supercafe-access">
-                <label class="form-check-label" for="supercafe-access">
-                  Acceso
-                </label>
+                <label class="form-check-label" for="supercafe-access">Acceso</label>
               </div>
               <div class="form-check">
                 <input class="form-check-input" type="checkbox" name="permissions[]" value="supercafe:edit" id="supercafe-edit">
-                <label class="form-check-label" for="supercafe-edit">
-                  Editar comandas
-                </label>
+                <label class="form-check-label" for="supercafe-edit">Editar comandas</label>
               </div>
             </div>
           </div>
@@ -183,13 +130,9 @@ switch ($_GET['action'] ?? '') {
         <label for="centro" class="form-label">Centro asociado:</label>
         <select id="centro" name="centro" class="form-select">
           <option value="">-- Selecciona un centro --</option>
-          <?php
-          $centros_folders_add = glob("/DATA/entreaulas/Centros/*", GLOB_ONLYDIR) ?: [];
-          foreach ($centros_folders_add as $centro_folder) {
-            $centro_id_opt = basename($centro_folder);
-            echo '<option value="' . htmlspecialchars($centro_id_opt) . '">' . htmlspecialchars($centro_id_opt) . '</option>';
-          }
-          ?>
+          <?php foreach ($all_centros as $cid): ?>
+            <option value="<?= htmlspecialchars($cid) ?>"><?= htmlspecialchars($cid) ?></option>
+          <?php endforeach; ?>
         </select>
       </div>
       <div class="mb-3">
@@ -205,112 +148,91 @@ switch ($_GET['action'] ?? '') {
   </div>
 </form>
 <?php
-    require_once "_incl/post-body.php";
-    break;
-  case 'edit':
-    require_once "_incl/pre-body.php";
-    $username = safe_username($_GET['user'] ?? '');
-    if (empty($username)) {
-      die("Nombre de usuario inválido.");
-    }
-    $user_file = get_user_file_path($username);
-    if (!file_exists($user_file) || !is_readable($user_file)) {
-      die("Usuario no encontrado o datos no disponibles.");
-    }
-    $jsonContent = file_get_contents($user_file);
-    if ($jsonContent === false) {
-      die("Error al leer los datos del usuario.");
-    }
-    $userdata = json_decode($jsonContent, true);
-    if (!is_array($userdata) || json_last_error() !== JSON_ERROR_NONE) {
-      die("Datos de usuario corruptos o con formato inválido.");
-    }
+        require_once "_incl/post-body.php";
+        break;
+
+    case 'edit':
+        require_once "_incl/pre-body.php";
+        $username = safe_username($_GET['user'] ?? '');
+        if (empty($username)) {
+            die("Nombre de usuario inválido.");
+        }
+        $row = db_get_user($username);
+        if (!$row) {
+            die("Usuario no encontrado.");
+        }
+        $userdata    = db_build_auth_data($row);
+        $all_centros = db_get_centro_ids();
+        $user_centro = safe_centro_id($userdata['entreaulas']['centro'] ?? '');
+        $aularios    = $user_centro !== '' ? db_get_aularios($user_centro) : [];
 ?>
 <form method="post" action="?form=save_edit">
   <div class="card pad">
     <div>
-      <h1>Editar Usuario: <?php echo htmlspecialchars($username); ?></h1>
+      <h1>Editar Usuario: <?= htmlspecialchars($username) ?></h1>
       <div class="mb-3">
         <label for="display_name" class="form-label">Nombre para mostrar:</label>
-        <input type="text" id="display_name" name="display_name" value="<?php echo htmlspecialchars($userdata['display_name'] ?? ''); ?>" class="form-control" required>
+        <input type="text" id="display_name" name="display_name" value="<?= htmlspecialchars($userdata['display_name'] ?? '') ?>" class="form-control" required>
       </div>
       <div class="mb-3">
         <label for="email" class="form-label">Correo electrónico:</label>
-        <input type="email" id="email" name="email" value="<?php echo htmlspecialchars($userdata['email'] ?? ''); ?>" class="form-control" required>
+        <input type="email" id="email" name="email" value="<?= htmlspecialchars($userdata['email'] ?? '') ?>" class="form-control" required>
       </div>
       <b>Permisos:</b>
       <div class="accordion mt-3" id="permissionsAccordion">
         <div class="accordion-item">
-          <h2 class="accordion-header" id="headingSysadmin">
-            <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSysadmin" aria-expanded="true" aria-controls="collapseSysadmin">
-              Administración del sistema
-            </button>
+          <h2 class="accordion-header">
+            <button class="accordion-button" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSysadmin">Administración del sistema</button>
           </h2>
-          <div id="collapseSysadmin" class="accordion-collapse collapse show" aria-labelledby="headingSysadmin" data-bs-parent="#permissionsAccordion">
+          <div id="collapseSysadmin" class="accordion-collapse collapse show" data-bs-parent="#permissionsAccordion">
             <div class="accordion-body">
               <div class="form-check">
-                <input class="form-check-input" type="checkbox" name="permissions[]" value="sysadmin:access" id="sysadmin-access" <?php if (in_array('sysadmin:access', $userdata['permissions'] ?? [])) echo 'checked'; ?>>
-                <label class="form-check-label" for="sysadmin-access">
-                  Acceso
-                </label>
+                <input class="form-check-input" type="checkbox" name="permissions[]" value="sysadmin:access" id="sysadmin-access" <?= in_array('sysadmin:access', $userdata['permissions'] ?? []) ? 'checked' : '' ?>>
+                <label class="form-check-label" for="sysadmin-access">Acceso</label>
               </div>
             </div>
           </div>
         </div>
         <div class="accordion-item">
-          <h2 class="accordion-header" id="headingEntreaulas">
-            <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseEntreaulas" aria-expanded="false" aria-controls="collapseEntreaulas">
-              EntreAulas
-            </button>
+          <h2 class="accordion-header">
+            <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseEntreaulas">EntreAulas</button>
           </h2>
-          <div id="collapseEntreaulas" class="accordion-collapse collapse" aria-labelledby="headingEntreaulas" data-bs-parent="#permissionsAccordion">
+          <div id="collapseEntreaulas" class="accordion-collapse collapse" data-bs-parent="#permissionsAccordion">
             <div class="accordion-body">
               <div class="form-check">
-                <input class="form-check-input" type="checkbox" name="permissions[]" value="entreaulas:access" id="entreaulas-access" <?php if (in_array('entreaulas:access', $userdata['permissions'] ?? [])) echo 'checked'; ?>>
-                <label class="form-check-label" for="entreaulas-access">
-                  Acceso
-                </label>
+                <input class="form-check-input" type="checkbox" name="permissions[]" value="entreaulas:access" id="entreaulas-access" <?= in_array('entreaulas:access', $userdata['permissions'] ?? []) ? 'checked' : '' ?>>
+                <label class="form-check-label" for="entreaulas-access">Acceso</label>
               </div>
               <div class="form-check">
-                <input class="form-check-input" type="checkbox" name="permissions[]" value="entreaulas:docente" id="entreaulas-docente" <?php if (in_array('entreaulas:docente', $userdata['permissions'] ?? [])) echo 'checked'; ?>>
-                <label class="form-check-label" for="entreaulas-docente">
-                  Docente
-                </label>
+                <input class="form-check-input" type="checkbox" name="permissions[]" value="entreaulas:docente" id="entreaulas-docente" <?= in_array('entreaulas:docente', $userdata['permissions'] ?? []) ? 'checked' : '' ?>>
+                <label class="form-check-label" for="entreaulas-docente">Docente</label>
               </div>
               <div class="form-check">
-                <input class="form-check-input" type="checkbox" name="permissions[]" value="entreaulas:proyectos:delete" id="entreaulas-proyectos-delete" <?php if (in_array('entreaulas:proyectos:delete', $userdata['permissions'] ?? [])) echo 'checked'; ?>>
-                <label class="form-check-label" for="entreaulas-proyectos-delete">
-                  Eliminar Proyectos
-                </label>
+                <input class="form-check-input" type="checkbox" name="permissions[]" value="entreaulas:proyectos:delete" id="entreaulas-proyectos-delete" <?= in_array('entreaulas:proyectos:delete', $userdata['permissions'] ?? []) ? 'checked' : '' ?>>
+                <label class="form-check-label" for="entreaulas-proyectos-delete">Eliminar Proyectos</label>
               </div>
             </div>
           </div>
         </div>
         <div class="accordion-item">
-          <h2 class="accordion-header" id="headingSupercafe">
-            <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSupercafe" aria-expanded="false" aria-controls="collapseSupercafe">
-              SuperCafe
-            </button>
+          <h2 class="accordion-header">
+            <button class="accordion-button collapsed" type="button" data-bs-toggle="collapse" data-bs-target="#collapseSupercafe">SuperCafe</button>
           </h2>
-          <div id="collapseSupercafe" class="accordion-collapse collapse" aria-labelledby="headingSupercafe" data-bs-parent="#permissionsAccordion">
+          <div id="collapseSupercafe" class="accordion-collapse collapse" data-bs-parent="#permissionsAccordion">
             <div class="accordion-body">
               <div class="form-check">
-                <input class="form-check-input" type="checkbox" name="permissions[]" value="supercafe:access" id="supercafe-access" <?php if (in_array('supercafe:access', $userdata['permissions'] ?? [])) echo 'checked'; ?>>
-                <label class="form-check-label" for="supercafe-access">
-                  Acceso
-                </label>
+                <input class="form-check-input" type="checkbox" name="permissions[]" value="supercafe:access" id="supercafe-access" <?= in_array('supercafe:access', $userdata['permissions'] ?? []) ? 'checked' : '' ?>>
+                <label class="form-check-label" for="supercafe-access">Acceso</label>
               </div>
               <div class="form-check">
-                <input class="form-check-input" type="checkbox" name="permissions[]" value="supercafe:edit" id="supercafe-edit" <?php if (in_array('supercafe:edit', $userdata['permissions'] ?? [])) echo 'checked'; ?>>
-                <label class="form-check-label" for="supercafe-edit">
-                  Editar comandas
-                </label>
+                <input class="form-check-input" type="checkbox" name="permissions[]" value="supercafe:edit" id="supercafe-edit" <?= in_array('supercafe:edit', $userdata['permissions'] ?? []) ? 'checked' : '' ?>>
+                <label class="form-check-label" for="supercafe-edit">Editar comandas</label>
               </div>
             </div>
           </div>
         </div>
       </div>
-      <input type="hidden" name="username" value="<?php echo htmlspecialchars($username); ?>">
+      <input type="hidden" name="username" value="<?= htmlspecialchars($username) ?>">
       <button type="submit" class="btn btn-primary mt-3">Guardar Cambios</button>
     </div>
   </div>
@@ -320,104 +242,81 @@ switch ($_GET['action'] ?? '') {
       <div class="mb-3">
         <label for="centro" class="form-label">Centro asociado:</label>
         <select id="centro" name="centro" class="form-select" required>
-          <option value="" <?php if (empty($userdata["entreaulas"]['centro'] ?? '')) echo 'selected'; ?>>-- Selecciona un centro --</option>
-          <?php
-          $centros_folders = glob("/DATA/entreaulas/Centros/*", GLOB_ONLYDIR);
-          foreach ($centros_folders as $centro_folder) {
-            $centro_id = basename($centro_folder);
-            echo '<option value="' . htmlspecialchars($centro_id) . '"';
-            if (($userdata["entreaulas"]['centro'] ?? '') === $centro_id) {
-              echo ' selected';
-            }
-            echo '>' . htmlspecialchars($centro_id) . '</option>';
-          }
-          ?>
+          <option value="" <?= empty($user_centro) ? 'selected' : '' ?>>-- Selecciona un centro --</option>
+          <?php foreach ($all_centros as $cid): ?>
+            <option value="<?= htmlspecialchars($cid) ?>" <?= $user_centro === $cid ? 'selected' : '' ?>><?= htmlspecialchars($cid) ?></option>
+          <?php endforeach; ?>
         </select>
       </div>
       <div class="mb-3">
         <label for="role" class="form-label">Rol en EntreAulas:</label>
         <select id="role" name="role" class="form-select" required>
-          <option value="" <?php if (empty($userdata["entreaulas"]['role'] ?? '')) echo 'selected'; ?>>-- Selecciona un rol --</option>
-          <option value="teacher" <?php if (($userdata["entreaulas"]['role'] ?? '') === 'teacher') echo 'selected'; ?>>Profesor</option>
-          <option value="student" <?php if (($userdata["entreaulas"]['role'] ?? '') === 'student') echo 'selected'; ?>>Estudiante</option>
+          <option value="" <?= empty($userdata['entreaulas']['role'] ?? '') ? 'selected' : '' ?>>-- Selecciona un rol --</option>
+          <option value="teacher" <?= ($userdata['entreaulas']['role'] ?? '') === 'teacher' ? 'selected' : '' ?>>Profesor</option>
+          <option value="student" <?= ($userdata['entreaulas']['role'] ?? '') === 'student' ? 'selected' : '' ?>>Estudiante</option>
         </select>
       </div>
       <div class="mb-3">
         <label class="form-label">Aulas asignadas: <small>(Guarda primero para actualizar la lista)</small></label><br>
-        <?php
-        $user_centro = safe_centro_id($userdata["entreaulas"]['centro'] ?? '');
-        $aulas_filelist = $user_centro !== '' ? (glob("/DATA/entreaulas/Centros/" . $user_centro . "/Aularios/*.json") ?: []) : [];
-        foreach ($aulas_filelist as $aula_file) {
-          $aula_data = json_decode(file_get_contents($aula_file), true);
-          $aula_id = safe_aulario_id(basename($aula_file, ".json"));
-          $is_assigned = in_array($aula_id, $userdata["entreaulas"]['aulas'] ?? []);
-          echo '<div class="form-check form-check-inline">';
-          echo '<input class="form-check-input" type="checkbox" name="aulas[]" value="' . htmlspecialchars($aula_id) . '" id="aula-' . htmlspecialchars($aula_id) . '" ' . ($is_assigned ? 'checked' : '') . '>';
-          echo '<label class="form-check-label" for="aula-' . htmlspecialchars($aula_id) . '">' . htmlspecialchars($aula_data['name'] ?? $aula_id) . '</label>';
-          echo '</div>';
-        }
-        ?>
+        <?php foreach ($aularios as $aula_id => $aula_data): ?>
+          <div class="form-check form-check-inline">
+            <input class="form-check-input" type="checkbox" name="aulas[]"
+                   value="<?= htmlspecialchars($aula_id) ?>"
+                   id="aula-<?= htmlspecialchars($aula_id) ?>"
+                   <?= in_array($aula_id, $userdata['entreaulas']['aulas'] ?? []) ? 'checked' : '' ?>>
+            <label class="form-check-label" for="aula-<?= htmlspecialchars($aula_id) ?>">
+              <?= htmlspecialchars($aula_data['name'] ?? $aula_id) ?>
+            </label>
+          </div>
+        <?php endforeach; ?>
       </div>
     </div>
   </div>
   <div class="card pad">
     <div>
       <h2>Cambiar contraseña</h2>
-      <p>Para cambiar la contraseña de este usuario, utiliza la herramienta de restablecimiento de contraseñas disponible en el siguiente enlace:</p>
-      <a href="/sysadmin/reset_password.php?user=<?php echo urlencode($username); ?>" class="btn btn-secondary">Restablecer Contraseña</a>
+      <a href="/sysadmin/reset_password.php?user=<?= urlencode($username) ?>" class="btn btn-secondary">Restablecer Contraseña</a>
     </div>
   </div>
 </form>
-  <?php
-    require_once "_incl/post-body.php";
-    break;
-  case "index":
-  default:
-    require_once "_incl/pre-body.php";
-  ?>
-    <div class="card pad">
-      <div>
-        <h1>Gestión de Usuarios</h1>
-        <p>Desde esta sección puedes gestionar los usuarios del sistema. Puedes agregar, editar o eliminar usuarios según sea necesario.</p>
-        <table class="table table-striped table-hover">
-          <thead class="table-dark">
-            <tr>
-              <th>Usuario</th>
-              <th>Nombre</th>
-              <th>Correo</th>
-              <th>
-                <a href="?action=add" class="btn btn-success">+ Nuevo</a>
-              </th>
-            </tr>
-          </thead>
-          <tbody>
-            <?php
-            $users_filelist = glob(USERS_DIR . '*.json') ?: [];
-            foreach ($users_filelist as $user_file) {
-              $userdata = json_decode(file_get_contents($user_file), true);
-              if (!is_array($userdata)) {
-                error_log("users.php: corrupted or unreadable user file: $user_file");
-                $userdata = [];
-              }
-              // Username is the filename without path and extension
-              $username = basename($user_file, ".json");
-              echo "<tr>";
-              echo "<td>" . htmlspecialchars($username) . "</td>";
-              echo "<td>" . htmlspecialchars($userdata['display_name'] ?? 'N/A') . "</td>";
-              echo "<td>" . htmlspecialchars($userdata['email'] ?? 'N/A') . "</td>";
-              echo "<td>";
-              echo '<a href="?action=edit&user=' . urlencode($username) . '" class="btn btn-primary">Editar</a> ';
-              echo '<a href="?action=delete&user=' . urlencode($username) . '" class="btn btn-danger">Eliminar</a>';
-              echo "</td>";
-              echo "</tr>";
-            }
-            ?>
-          </tbody>
-        </table>
-      </div>
-    </div>
 <?php
-    require_once "_incl/post-body.php";
-    break;
+        require_once "_incl/post-body.php";
+        break;
+
+    case 'index':
+    default:
+        require_once "_incl/pre-body.php";
+        $all_users = db_get_all_users();
+?>
+<div class="card pad">
+  <div>
+    <h1>Gestión de Usuarios</h1>
+    <p>Desde esta sección puedes gestionar los usuarios del sistema.</p>
+    <table class="table table-striped table-hover">
+      <thead class="table-dark">
+        <tr>
+          <th>Usuario</th>
+          <th>Nombre</th>
+          <th>Correo</th>
+          <th><a href="?action=add" class="btn btn-success">+ Nuevo</a></th>
+        </tr>
+      </thead>
+      <tbody>
+        <?php foreach ($all_users as $u): ?>
+          <tr>
+            <td><?= htmlspecialchars($u['username']) ?></td>
+            <td><?= htmlspecialchars($u['display_name'] ?: 'N/A') ?></td>
+            <td><?= htmlspecialchars($u['email'] ?: 'N/A') ?></td>
+            <td>
+              <a href="?action=edit&user=<?= urlencode($u['username']) ?>" class="btn btn-primary">Editar</a>
+            </td>
+          </tr>
+        <?php endforeach; ?>
+      </tbody>
+    </table>
+  </div>
+</div>
+<?php
+        require_once "_incl/post-body.php";
+        break;
 }
-?>
\ No newline at end of file