:root {
    --primary-color: #0d6efd;
    --primary-hover: #0b5ed7;
    --bg-light: #f8f9fa;
    --text-dark: #212529;
    --text-muted: #6c757d;
    --card-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
    --card-shadow-hover: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
}

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    line-height: 1.7;
    color: var(--text-dark);
    background-color: #fff;
    padding-top: 76px;
}

/* Navbar moderne avec effet Glassmorphism */
.navbar {
    background: rgba(255, 255, 255, 0.95) !important;
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0,0,0,0.1);
    transition: all 0.3s ease;
}

.navbar-brand {
    font-weight: 700;
    color: var(--primary-color) !important;
    letter-spacing: -0.5px;
}

.nav-link {
    font-weight: 500;
    color: var(--text-dark) !important;
    transition: color 0.2s;
}

.nav-link:hover, .nav-link.active {
    color: var(--primary-color) !important;
}

/* Header stylisé */
header {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    border-radius: 0 0 2rem 2rem;
    margin-bottom: 3rem;
}

.display-4 {
    letter-spacing: -1px;
    color: #1a1e21;
}

/* Cartes et Sections */
.card {
    border: 1px solid rgba(0,0,0,0.05);
    border-radius: 1rem;
    box-shadow: var(--card-shadow);
    transition: all 0.3s ease;
    overflow: hidden;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--card-shadow-hover);
}

.section-title {
    position: relative;
    padding-bottom: 10px;
    margin-bottom: 20px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 50px;
    height: 3px;
    background: var(--primary-color);
    border-radius: 2px;
}

/* Boutons Google Play */
.btn-play {
    background: #000;
    color: #fff;
    border-radius: 0.75rem;
    padding: 0.6rem 1.5rem;
    font-weight: 600;
    border: none;
    transition: transform 0.2s;
}

.btn-play:hover {
    color: #fff;
    background: #222;
    transform: scale(1.05);
}

/* Accordéon personnalisé */
.accordion-item {
    border: none;
    margin-bottom: 1rem;
    background: transparent;
}

.accordion-button {
    border-radius: 0.75rem !important;
    font-weight: 600;
    box-shadow: var(--card-shadow);
}

.accordion-button:not(.collapsed) {
    background-color: #e7f1ff;
    color: var(--primary-color);
}

/* Back to Top */
#backToTop {
    display: none;
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--primary-color);
    color: white;
    border: none;
    box-shadow: 0 4px 15px rgba(13, 110, 253, 0.3);
    cursor: pointer;
    z-index: 1000;
    transition: all 0.3s ease;
}

#backToTop:hover {
    background: var(--primary-hover);
    transform: scale(1.1);
}

/* Footer */
footer {
    background: #1a1e21;
    color: #adb5bd;
    border-top: 4px solid var(--primary-color);
}

/* Responsive */
@media (max-width: 768px) {
    body { padding-top: 66px; }
    .display-4 { font-size: 2.5rem; }
}