:root {
    --primary-color: #0078d4; /* Bleu Azure */
    --dark-bg: #1a1a1a;
    --light-text: #f4f4f4;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    line-height: 1.6;
    background-color: var(--light-text);
    color: #333;
}

header {
    background: var(--dark-bg);
    color: white;
    padding: 1rem 5%;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

nav ul {
    display: flex;
    list-style: none;
}

nav ul li {
    margin-left: 20px;
}

nav a {
    color: white;
    text-decoration: none;
    font-weight: bold;
}

.hero {
    height: 60vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    background: linear-gradient(rgba(0,0,0,0.7), rgba(0,0,0,0.7)), url('https://images.unsplash.com/photo-1517694712202-14dd9538aa97?auto=format&fit=crop&w=800&q=80');
    background-size: cover;
    color: white;
}

.hero h1 span {
    color: var(--primary-color);
}

.btn {
    margin-top: 20px;
    padding: 10px 25px;
    background: var(--primary-color);
    color: white;
    text-decoration: none;
    border-radius: 5px;
    transition: 0.3s;
}

.btn:hover {
    background: #005a9e;
}