GNU nano 8.4                          login.php
<?php
session_start();
require '../config/db.php';
$env = require '../config/env.php';

$data = json_decode(file_get_contents('php://input'), true);
$username = trim($data['username'] ?? '');
$password = $data['password'] ?? '';

$stmt = $pdo->prepare("SELECT * FROM utilisateurs WHERE pseudo = ?");
$stmt->execute([$username]);
$user = $stmt->fetch(PDO::FETCH_ASSOC);

if (!$user || !password_verify($password, $user['mot_de_passe'])) {
    echo json_encode(['success'=>false,'message'=>'Identifiants incorrects']);
    exit;
}

$_SESSION['user_id'] = $user['id'];
$isAdmin = strtolower($user['pseudo']) === 'admin';

echo json_encode([
    'success'=>true,
    'message'=>'Connexion réussie',
    'isAdmin'=>$isAdmin,
    'flag'=>$isAdmin ? $env['FLAG'] : null
]);