body {
    font-family: Arial, Helvetica, sans-serif;
    margin: 0;
    padding: 0;
    background: #f5f7fa;
    color: #333;
}

a {
    color: #4f46e5;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* Page d'accueil */
.en-tete {
    text-align: center;
    background: linear-gradient(135deg, #4f46e5, #7c3aed);
    color: white;
    padding: 60px 20px;
    margin: 20px;
    border-radius: 20px;
}

.en-tete h2 {
    font-size: 2.2em;
    margin: 0 0 10px 0;
}

.en-tete p {
    font-size: 1.2em;
    margin: 0;
    opacity: 0.9;
}

.content {
    text-align: center;
    padding: 30px 20px;
}

.content h3 {
    font-size: 1.8em;
    color: #4f46e5;
    margin: 20px 0;
}

.college, .lycee {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-wrap: wrap;
    gap: 15px;
    margin: 10px 0;
}

.college button, .lycee button {
    border: none;
    border-radius: 30px;
    padding: 12px 30px;
    font-size: 1.1em;
    font-weight: bold;
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    cursor: pointer;
    transition: 0.2s;
}

.college button:hover, .lycee button:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 15px rgba(79, 70, 229, 0.4);
}

hr {
    width: 80%;
    max-width: 600px;
    border: none;
    border-top: 2px solid #4f46e5;
    margin: 30px auto;
}

/* Page présentation */
.enseignants {
    max-width: 800px;
    margin: 40px auto;
    padding: 0 20px;
}

.enseignants h2 {
    text-align: center;
    font-size: 2em;
    color: #4f46e5;
    margin-bottom: 30px;
}

.enseignants p {
    font-size: 1.15em;
    line-height: 1.8;
}

.bleu {
    color: #4f46e5;
    font-weight: bold;
}

/* Pages niveaux */
.niveau-entete {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    text-align: center;
    padding: 50px 20px;
    margin: 20px;
    border-radius: 20px;
}

.niveau-entete h1 {
    font-size: 2.5em;
    margin: 0;
}

.niveau-entete p {
    font-size: 1.1em;
    opacity: 0.9;
    margin: 10px 0 0 0;
}

.niveau-placeholder {
    text-align: center;
    padding: 80px 20px;
    color: #999;
    font-size: 1.2em;
}

/* Footer */
.credits {
    display: flex;
    justify-content: space-between;
    padding: 20px 40px;
    margin-top: 60px;
    border-top: 2px solid #4f46e5;
    color: #4f46e5;
    font-weight: bold;
}

/* Responsive pour téléphone */
@media (max-width: 600px) {
    header {
        flex-wrap: wrap;
        padding: 10px 15px;
    }
    header h1 {
        font-size: 1.2em;
    }
    header nav a {
        margin-left: 10px;
        font-size: 0.9em;
    }
    .en-tete h2 {
        font-size: 1.5em;
    }
    .en-tete p {
        font-size: 1em;
    }
    .college button, .lycee button {
        padding: 10px 20px;
        font-size: 1em;
    }
}