:root {
    --bg-color: #e8ecf1;
    --card-bg: #ffffff;
    --text-main: #1e2229;
    --text-muted: #57657b;
    --border-color: #cbd5e1;
    
    --carbon: #1e2229;
    --forest: #166534;
    --code: #15803d;
    --electric: #7c3aed;
    
    --font-sans: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: var(--font-sans);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 8%;
    background-color: rgba(232, 236, 241, 0.9);
    backdrop-filter: blur(8px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.logo {
    font-size: 1.15rem;
    font-weight: 800;
    color: var(--carbon);
    text-decoration: none;
    letter-spacing: -0.5px;
}

.logo span {
    color: var(--electric);
}

nav ul {
    display: flex;
    list-style: none;
    gap: 2.5rem;
}

nav a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.2s ease;
    font-size: 0.95rem;
    font-weight: 500;
}

nav a:hover, nav a.active {
    color: var(--electric);
}

main {
    max-width: 1100px;
    margin: 0 auto;
    padding: 5rem 2rem;
}

.page {
    display: none;
}

.page.active {
    display: block;
    animation: fadeIn 0.3s ease-in-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(6px); }
    to { opacity: 1; transform: translateY(0); }
}

.hero {
    text-align: center;
    padding: 4rem 0 6rem 0;
}

.hero h1 {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 1.2rem;
    color: var(--carbon);
    letter-spacing: -1px;
    line-height: 1.2;
}

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

.hero p {
    color: var(--text-muted);
    max-width: 600px;
    margin: 0 auto 2.5rem auto;
    font-size: 1.15rem;
}

.btn {
    display: inline-block;
    background: var(--electric);
    color: #ffffff;
    border: none;
    padding: 0.8rem 1.8rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    box-shadow: 0 4px 14px rgba(124, 58, 237, 0.25);
    transition: background 0.2s ease, transform 0.1s ease, box-shadow 0.2s ease;
}

.btn:hover {
    background: #6d28d9;
    transform: translateY(-1px);
    box-shadow: 0 6px 20px rgba(124, 58, 237, 0.35);
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2.5rem;
    position: relative;
    overflow: hidden;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.03);
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
}

.card.card-opensource::before { background-color: var(--code); }
.card.card-game::before { background-color: var(--electric); }
.card.card-3d::before { background-color: var(--forest); }

.card:hover {
    transform: translateY(-4px);
    border-color: #94a3b8;
    box-shadow: 0 12px 30px -10px rgba(30, 34, 41, 0.1);
}

.card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    color: var(--carbon);
}

.card p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
}

.btn-card-opensource {
    background: transparent;
    color: var(--code);
    border: 1px solid var(--code);
    box-shadow: none;
}
.btn-card-opensource:hover {
    background: var(--code);
    color: #ffffff;
}

.btn-card-game {
    background: transparent;
    color: var(--electric);
    border: 1px solid var(--electric);
    box-shadow: none;
}
.btn-card-game:hover {
    background: var(--electric);
    color: #ffffff;
}

.btn-card-3d {
    background: transparent;
    color: var(--forest);
    border: 1px solid var(--forest);
    box-shadow: none;
}
.btn-card-3d:hover {
    background: var(--forest);
    color: #ffffff;
}

.content-box {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 3.5rem;
    max-width: 750px;
    margin: 0 auto;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.03);
}

.content-box h2 {
    font-size: 2rem;
    margin-bottom: 1.5rem;
    color: var(--carbon);
    letter-spacing: -0.5px;
}

.content-box p {
    color: var(--text-muted);
    margin-bottom: 1.2rem;
    font-size: 1.05rem;
}

footer {
    text-align: center;
    padding: 3rem 2rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-top: 6rem;
    background-color: rgba(232, 236, 241, 0.5);
}

/* Style pour séparer la carte en deux colonnes */
.card-split {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.card-content {
    flex: 1;
}

.card-image {
    flex: 1;
    min-height: 220px;
}

/* S'adapte automatiquement sur les écrans plus petits (mobiles) */
@media (max-width: 768px) {
    .card-split {
        flex-direction: column;
    }
}