body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            line-height: 1.6;
            color: #2d3748;
            overflow-x: hidden;
        }

        /* ========== NAVBAR ========== */
        .navbar {
            position: fixed;
            top: 0; left: 0; right: 0;
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(12px);
            padding: 0.85rem 2rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
            z-index: 1000;
            box-shadow: 0 1px 12px rgba(0, 0, 0, 0.06);
            transition: transform 0.3s ease;
        }
        .navbar.hidden { transform: translateY(-100%); }
        .navbar-logo {
            display: flex;
            align-items: center;
            gap: 0.35rem;
            text-decoration: none;
        }
        .navbar-logo-icon {
            height: 46px;
            width: auto;
            margin: -8px 0;
        }
        .navbar-logo-collect {
            font-size: 1.3rem;
            font-weight: 800;
            font-style: italic;
            color: #667eea;
        }
        .navbar-logo-theque {
            font-size: 1.3rem;
            font-weight: 800;
            font-style: italic;
            color: #ffd700;
            margin-left: -0.25rem;
        }
        .navbar-actions { display: flex; gap: 0.75rem; align-items: center; }
        .navbar-btn {
            padding: 0.55rem 1.25rem;
            border-radius: 10px;
            border: none;
            cursor: pointer;
            font-size: 0.9rem;
            font-weight: 600;
            transition: all 0.2s;
        }
        .navbar-btn-ghost { background: none; color: #4a5568; }
        .navbar-btn-ghost:hover { color: #667eea; }
        .navbar-btn-primary {
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
        }
        .navbar-btn-primary:hover { transform: translateY(-1px); box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4); }
        .navbar-btn-label-short { display: none; }

        /* ========== HERO ========== */
        .hero {
            min-height: 100vh;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            display: flex;
            align-items: center;
            justify-content: center;
            text-align: center;
            padding: 6rem 2rem 4rem;
            position: relative;
            overflow: hidden;
        }
        .hero::before {
            content: '';
            position: absolute;
            top: -50%; left: -50%;
            width: 200%; height: 200%;
            background: radial-gradient(circle at 30% 50%, rgba(255,255,255,0.08) 0%, transparent 50%),
                        radial-gradient(circle at 70% 80%, rgba(255,255,255,0.05) 0%, transparent 40%);
            animation: heroFloat 20s ease-in-out infinite;
        }
        @keyframes heroFloat {
            0%, 100% { transform: translate(0, 0); }
            50% { transform: translate(-2%, 2%); }
        }

        /* ========== ANIMATIONS HOMEPAGE ========== */
        @keyframes heroFadeUp {
            from { opacity: 0; transform: translateY(20px); }
            to   { opacity: 1; transform: translateY(0); }
        }
        @keyframes heroFadeDown {
            from { opacity: 0; transform: translateY(-14px); }
            to   { opacity: 1; transform: translateY(0); }
        }
        @keyframes heroScaleIn {
            from { opacity: 0; transform: scale(0.85); }
            to   { opacity: 1; transform: scale(1); }
        }
        @keyframes logoEntrance {
            0%   { opacity: 0; transform: scale(0)   rotate(-180deg); }
            60%  { opacity: 1; transform: scale(1.12) rotate(10deg);  }
            80%  {              transform: scale(0.96) rotate(-4deg); }
            100% { opacity: 1; transform: scale(1)    rotate(0);      }
        }
        @keyframes stepPulse {
            0%, 100% { box-shadow: 0 4px 16px rgba(102, 126, 234, 0.25); }
            50%      { box-shadow: 0 6px 28px rgba(102, 126, 234, 0.45); }
        }

        /* Entrée en cascade du hero */
        .hero-logo-wrap { animation: logoEntrance 1.1s cubic-bezier(0.34, 1.56, 0.64, 1) both; }
        .hero-wordmark { animation: heroFadeDown 0.7s ease-out 0.15s both; }
        .hero-badge    { animation: heroFadeUp 0.6s ease-out 0.3s both; }
        .hero h1       { animation: heroFadeUp 0.7s ease-out 0.4s both; }
        .hero-subtitle { animation: heroFadeUp 0.7s ease-out 0.55s both; }
        .hero-actions  { animation: heroFadeUp 0.7s ease-out 0.7s both; }

        /* Révélation au scroll (déclenchée par JS via .is-visible) */
        .reveal {
            opacity: 0;
            transform: translateY(30px);
            transition: opacity 0.7s ease-out, transform 0.7s ease-out;
            will-change: opacity, transform;
        }
        .reveal.is-visible {
            opacity: 1;
            transform: translateY(0);
        }
        /* Stagger : les enfants révélés apparaissent en cascade de 100ms */
        .reveal.stagger > * {
            opacity: 0;
            transform: translateY(24px);
            transition: opacity 0.6s ease-out, transform 0.6s ease-out;
        }
        .reveal.stagger.is-visible > *              { opacity: 1; transform: translateY(0); }
        .reveal.stagger.is-visible > *:nth-child(1) { transition-delay: 0.00s; }
        .reveal.stagger.is-visible > *:nth-child(2) { transition-delay: 0.08s; }
        .reveal.stagger.is-visible > *:nth-child(3) { transition-delay: 0.16s; }
        .reveal.stagger.is-visible > *:nth-child(4) { transition-delay: 0.24s; }
        .reveal.stagger.is-visible > *:nth-child(5) { transition-delay: 0.32s; }
        .reveal.stagger.is-visible > *:nth-child(6) { transition-delay: 0.40s; }

        /* Enrichir le hover des cards */
        .feature-card, .gift-feature, .step { will-change: transform; }
        .feature-card:hover   { transform: translateY(-8px) scale(1.02); }
        .gift-feature:hover   { transform: translateY(-6px); transition: transform 0.3s ease; }
        .step:hover .step-number { animation: stepPulse 1.4s ease-in-out infinite; transform: scale(1.08); transition: transform 0.3s ease; }

        /* Respect des préférences d'accessibilité */
        @media (prefers-reduced-motion: reduce) {
            .hero-logo-wrap, .hero-logo, .hero-wordmark, .hero-badge, .hero h1, .hero-subtitle, .hero-actions,
            .reveal, .reveal.stagger > * { animation: none !important; transition: none !important; opacity: 1 !important; transform: none !important; }
        }
        .hero-content { position: relative; z-index: 1; max-width: 800px; }
        .hero-top {
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 1rem;
            margin-bottom: 2rem;
        }
        .hero-logo-wrap {
            position: relative;
            /* Ratio aligné sur le GIF (317:283 ≈ 1.12) pour qu'il remplisse entièrement.
               Le PNG étant quasi carré (712:707), il apparaît avec quelques pixels de letterbox
               horizontal invisibles à l'œil. */
            width: 135px;
            aspect-ratio: 317 / 283;
            flex-shrink: 0;
            cursor: pointer;
        }
        .hero-logo {
            position: absolute;
            inset: 0;
            width: 100%;
            height: 100%;
            object-fit: contain;
            filter: drop-shadow(0 4px 16px rgba(0, 0, 0, 0.25));
            transition: opacity 0.3s ease;
        }
        .hero-logo-animated {
            opacity: 0;
            /* Le GIF remplit toute la largeur du wrap alors que le PNG (quasi carré) est
               height-constrained. On réduit la largeur et on étire légèrement la hauteur
               pour qu'il corresponde visuellement à la taille rendue du PNG. */
            transform: scale(0.9, 0.95);
        }
        .hero-logo-wrap:hover .hero-logo-still    { opacity: 0; }
        .hero-logo-wrap:hover .hero-logo-animated { opacity: 1; }
        .hero-wordmark {
            font-size: 2.6rem;
            font-weight: 800;
            font-style: italic;
            letter-spacing: 0.5px;
            line-height: 1;
        }
        .hero-wordmark-collect { color: #ffffff; }
        .hero-wordmark-theque { color: #ffd700; margin-left: 0.1rem; }
        .hero-badge {
            display: inline-block;
            background: rgba(255, 255, 255, 0.15);
            backdrop-filter: blur(8px);
            color: white;
            padding: 0.4rem 1.25rem;
            border-radius: 50px;
            font-size: 0.85rem;
            font-weight: 500;
            border: 1px solid rgba(255, 255, 255, 0.2);
        }
        .hero h1 {
            font-size: 3.5rem;
            font-weight: 800;
            color: white;
            line-height: 1.15;
            margin-bottom: 1.5rem;
        }
        .hero h1 span {
            background: linear-gradient(90deg, #ffd700, #ffb347);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .hero-subtitle {
            font-size: 1.2rem;
            color: rgba(255, 255, 255, 0.85);
            margin-bottom: 2.5rem;
            max-width: 600px;
            margin-left: auto;
            margin-right: auto;
            line-height: 1.7;
        }
        .hero-actions { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }
        .hero-btn {
            padding: 0.9rem 2rem;
            border-radius: 14px;
            border: none;
            cursor: pointer;
            font-size: 1rem;
            font-weight: 600;
            transition: all 0.3s;
            text-decoration: none;
        }
        .hero-btn-primary {
            background: white;
            color: #667eea;
        }
        .hero-btn-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 30px rgba(0,0,0,0.2); }
        .hero-btn-ghost {
            background: rgba(255,255,255,0.15);
            color: white;
            border: 1px solid rgba(255,255,255,0.3);
            backdrop-filter: blur(4px);
        }
        .hero-btn-ghost:hover { background: rgba(255,255,255,0.25); }

        .hero-stats {
            display: flex;
            justify-content: center;
            gap: 3rem;
            margin-top: 4rem;
            flex-wrap: wrap;
        }
        .hero-stat { text-align: center; color: white; }
        .hero-stat-value { font-size: 2rem; font-weight: 800; }
        .hero-stat-label { font-size: 0.85rem; opacity: 0.75; margin-top: 0.25rem; }

        /* ========== SECTIONS ========== */
        section { padding: 5rem 2rem; }
        .section-header { text-align: center; max-width: 650px; margin: 0 auto 3.5rem; }
        .section-header h2 { font-size: 2.2rem; font-weight: 800; color: #2d3748; margin-bottom: 1rem; }
        .section-header p { font-size: 1.1rem; color: #718096; line-height: 1.7; }

        /* ========== FEATURES ========== */
        .features { background: #f7fafc; }
        .features-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 2rem;
            max-width: 1100px;
            margin: 0 auto;
        }
        .feature-card {
            background: white;
            border-radius: 20px;
            padding: 2rem;
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
            transition: all 0.3s;
            border: 1px solid transparent;
        }
        .feature-card:hover {
            transform: translateY(-6px);
            box-shadow: 0 12px 40px rgba(102, 126, 234, 0.12);
            border-color: rgba(102, 126, 234, 0.15);
        }
        .feature-icon {
            width: 56px; height: 56px;
            border-radius: 14px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.6rem;
            margin-bottom: 1.25rem;
        }
        .feature-card h3 { font-size: 1.15rem; font-weight: 700; color: #2d3748; margin-bottom: 0.5rem; }
        .feature-card p { font-size: 0.92rem; color: #718096; line-height: 1.6; }

        /* ========== HOW IT WORKS ========== */
        .how-it-works { background: white; }
        .steps {
            display: flex;
            gap: 2rem;
            max-width: 1000px;
            margin: 0 auto;
            flex-wrap: wrap;
            justify-content: center;
        }
        .step {
            flex: 1;
            min-width: 220px;
            text-align: center;
            position: relative;
        }
        .step-number {
            width: 52px; height: 52px;
            border-radius: 50%;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            font-size: 1.3rem;
            font-weight: 700;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 1.25rem;
        }
        .step h3 { font-size: 1.1rem; font-weight: 700; color: #2d3748; margin-bottom: 0.5rem; }
        .step p { font-size: 0.9rem; color: #718096; line-height: 1.5; }

        /* ========== GIFT SECTION ========== */
        .gift-section {
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            text-align: center;
        }
        .gift-section h2 { color: white; font-size: 2.2rem; font-weight: 800; margin-bottom: 1rem; }
        .gift-section p { color: rgba(255,255,255,0.85); font-size: 1.1rem; max-width: 600px; margin: 0 auto 2.5rem; line-height: 1.7; }
        .gift-features {
            display: flex;
            gap: 2rem;
            max-width: 900px;
            margin: 0 auto;
            flex-wrap: wrap;
            justify-content: center;
        }
        .gift-feature {
            background: rgba(255,255,255,0.1);
            backdrop-filter: blur(8px);
            border: 1px solid rgba(255,255,255,0.15);
            border-radius: 20px;
            padding: 2rem;
            flex: 1;
            min-width: 240px;
            max-width: 280px;
        }
        .gift-feature-icon { font-size: 2.5rem; margin-bottom: 1rem; }
        .gift-feature h3 { font-size: 1.1rem; font-weight: 600; margin-bottom: 0.5rem; }
        .gift-feature p { font-size: 0.9rem; opacity: 0.8; line-height: 1.5; }

        /* ========== CTA FINAL ========== */
        .cta-section { background: #f7fafc; text-align: center; padding: 5rem 2rem; }
        .cta-section h2 { font-size: 2.2rem; font-weight: 800; color: #2d3748; margin-bottom: 1rem; }
        .cta-section p { font-size: 1.1rem; color: #718096; margin-bottom: 2rem; max-width: 500px; margin-left: auto; margin-right: auto; }
        .cta-btn {
            padding: 1rem 2.5rem;
            border-radius: 14px;
            border: none;
            cursor: pointer;
            font-size: 1.05rem;
            font-weight: 700;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            transition: all 0.3s;
        }
        .cta-btn:hover { transform: translateY(-2px); box-shadow: 0 12px 30px rgba(102, 126, 234, 0.4); }

        /* ========== FOOTER ========== */
        .footer {
            background: #1a202c;
            color: rgba(255,255,255,0.6);
            padding: 3rem 2rem;
        }
        .footer-content {
            max-width: 1100px;
            margin: 0 auto;
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 1.5rem;
        }
        .footer-logo {
            font-size: 1.3rem;
            font-weight: 700;
            color: white;
            text-decoration: none;
        }
        .footer-links { display: flex; gap: 1.5rem; flex-wrap: wrap; }
        .footer-links a { color: rgba(255,255,255,0.5); text-decoration: none; font-size: 0.9rem; transition: color 0.2s; }
        .footer-links a:hover { color: white; }
        .footer-copy { font-size: 0.85rem; }

        /* ========== AUTH POPUP ========== */
        .popup-overlay {
            display: none;
            position: fixed;
            top: 0; left: 0; right: 0; bottom: 0;
            background: rgba(0, 0, 0, 0.5);
            backdrop-filter: blur(4px);
            z-index: 2000;
            align-items: center;
            justify-content: center;
        }
        .popup-overlay.active { display: flex; }
        .popup-container {
            background: white;
            border-radius: 24px;
            padding: 2.5rem;
            max-width: 420px;
            width: 90%;
            position: relative;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.2);
            max-height: 90vh;
            overflow-y: auto;
        }
        .popup-close {
            position: absolute;
            top: 1rem; right: 1rem;
            background: none;
            border: none;
            font-size: 1.5rem;
            cursor: pointer;
            color: #a0aec0;
            width: 36px; height: 36px;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 50%;
        }
        .popup-close:hover { background: #f7fafc; color: #2d3748; }
        .auth-tabs { display: flex; gap: 0.5rem; margin-bottom: 1.5rem; }
        .auth-tab {
            flex: 1;
            padding: 0.65rem;
            border: none;
            background: #f7fafc;
            border-radius: 10px;
            cursor: pointer;
            font-weight: 600;
            color: #718096;
            font-size: 0.95rem;
            transition: all 0.2s;
        }
        .auth-tab.active { background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); color: white; }
        .auth-form { display: none; }
        .auth-form.active { display: block; }
        .form-group { margin-bottom: 1.25rem; }
        .form-group label { display: block; font-weight: 600; color: #4a5568; margin-bottom: 0.4rem; font-size: 0.9rem; }
        .form-group input {
            width: 100%;
            padding: 0.7rem 1rem;
            border: 2px solid #e2e8f0;
            border-radius: 10px;
            font-size: 0.95rem;
            transition: border-color 0.2s;
        }
        .form-group input:focus { outline: none; border-color: #667eea; }
        .form-group input.error { border-color: #e53e3e; }
        .form-group input.error:focus { border-color: #e53e3e; }
        .error-message { color: #e53e3e; font-size: 0.8rem; margin-top: 0.3rem; display: none; }
        .error-message.active { display: block; }
        .form-submit {
            width: 100%;
            padding: 0.75rem;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            border: none;
            border-radius: 10px;
            font-size: 0.95rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.2s;
        }
        .form-submit:hover { transform: translateY(-1px); box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4); }
        .alert { padding: 0.85rem 1rem; border-radius: 10px; font-size: 0.9rem; margin-bottom: 1rem; }
        .alert-success { background: #f0fff4; color: #22543d; border: 1px solid #c6f6d5; }
        .alert-error { background: #fff5f5; color: #c53030; border: 1px solid #fed7d7; }

        /* ========== RESPONSIVE ========== */
        @media (max-width: 768px) {
            .hero h1 { font-size: 2.2rem; }
            .hero-subtitle { font-size: 1rem; }
            .hero-logo-wrap { width: 95px; }
            .hero-wordmark { font-size: 2rem; }
            .hero-top { gap: 0.75rem; margin-bottom: 1.5rem; }
            .hero-stats { gap: 1.5rem; }
            .features-grid { grid-template-columns: 1fr; max-width: 400px; }
            .steps { flex-direction: column; align-items: center; }
            .gift-features { flex-direction: column; align-items: center; }
            .section-header h2 { font-size: 1.7rem; }
            .footer-content { flex-direction: column; text-align: center; }
            .navbar-btn-ghost { display: none; }
            .navbar { padding: 0.65rem 1rem; }
            .navbar-logo-icon { height: 38px; }
            .navbar-logo-collect, .navbar-logo-theque { font-size: 1.1rem; }
            .navbar-btn { padding: 0.45rem 0.85rem; font-size: 0.85rem; }
            .navbar-btn-label-long { display: none; }
            .navbar-btn-label-short { display: inline; }
        }