/* ======================
   Styles généraux
   ====================== */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
    overflow: hidden;
}

/* ======================
   En-tête
   ====================== */

header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 30px;
    text-align: center;
}

header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.subtitle {
    font-size: 1.1em;
    opacity: 0.9;
}

/* ======================
   Navigation
   ====================== */

nav {
    background: #f8f9fa;
    padding: 15px 30px;
    border-bottom: 1px solid #e0e0e0;
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

/* ======================
   Boutons
   ====================== */

.btn {
    padding: 10px 20px;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 500;
    display: inline-block;
    transition: all 0.3s ease;
    border: none;
    cursor: pointer;
    font-size: 1em;
}

.btn-primary {
    background: #667eea;
    color: white;
}

.btn-primary:hover {
    background: #5568d3;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(102, 126, 234, 0.3);
}

.btn-success {
    background: #28a745;
    color: white;
}

.btn-success:hover {
    background: #218838;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(40, 167, 69, 0.3);
}

.btn-secondary {
    background: #6c757d;
    color: white;
}

.btn-secondary:hover {
    background: #5a6268;
}

/* ======================
   Contenu principal
   ====================== */

main {
    padding: 30px;
}

main h2 {
    color: #333;
    margin-bottom: 20px;
    font-size: 1.8em;
    border-bottom: 3px solid #667eea;
    padding-bottom: 10px;
}

/* ======================
   Alertes
   ====================== */

.alert {
    padding: 15px 20px;
    border-radius: 5px;
    margin-bottom: 20px;
    border-left: 4px solid;
}

.alert h3 {
    margin-bottom: 10px;
    font-size: 1.1em;
}

.alert ul {
    margin-left: 20px;
}

.alert-info {
    background: #d1ecf1;
    color: #0c5460;
    border-left-color: #17a2b8;
}

.alert-error {
    background: #f8d7da;
    color: #721c24;
    border-left-color: #dc3545;
}

.alert-success {
    background: #d4edda;
    color: #155724;
    border-left-color: #28a745;
}

/* ======================
   Liste des messages
   ====================== */

.messages-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.message-card {
    background: #f8f9fa;
    border-radius: 10px;
    padding: 20px;
    border-left: 5px solid #667eea;
    transition: all 0.3s ease;
}

.message-card:hover {
    transform: translateX(5px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.message-header {
    margin-bottom: 15px;
}

.message-subject {
    color: #333;
    font-size: 1.4em;
    margin-bottom: 8px;
}

.message-meta {
    color: #6c757d;
    font-size: 0.9em;
}

.message-meta strong {
    color: #667eea;
}

.message-content {
    color: #555;
    line-height: 1.6;
}

.message-content p {
    margin: 0;
}

/* ======================
   Formulaire
   ====================== */

.message-form {
    background: #f8f9fa;
    padding: 25px;
    border-radius: 10px;
    margin-top: 20px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: #333;
}

.form-group input[type="text"],
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 2px solid #e0e0e0;
    border-radius: 5px;
    font-size: 1em;
    font-family: inherit;
    transition: border-color 0.3s ease;
}

.form-group input[type="text"]:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 150px;
}

.form-actions {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    margin-top: 25px;
}

/* ======================
   Pied de page
   ====================== */

footer {
    background: #2c3e50;
    color: white;
    text-align: center;
    padding: 20px;
    margin-top: 30px;
}

/* ======================
   Responsive
   ====================== */

@media (max-width: 768px) {
    body {
        padding: 10px;
    }
    
    header h1 {
        font-size: 2em;
    }
    
    main {
        padding: 20px;
    }
    
    nav {
        padding: 15px;
    }
    
    .message-form {
        padding: 15px;
    }
}