/* roulang page: index */
:root {
            --bg-primary: #06060f;
            --bg-secondary: #0c0c1d;
            --bg-card: #111128;
            --bg-card-hover: #16163a;
            --neon-blue: #00d4ff;
            --neon-purple: #a855f7;
            --neon-pink: #ff2d95;
            --neon-cyan: #00f0c8;
            --text-primary: #f0f0f5;
            --text-secondary: #c5c5d8;
            --text-muted: #8888a8;
            --border-subtle: rgba(255, 255, 255, 0.08);
            --border-glow: rgba(0, 212, 255, 0.35);
            --border-purple: rgba(168, 85, 247, 0.4);
            --radius-sm: 0.5rem;
            --radius-md: 0.75rem;
            --radius-lg: 1rem;
            --radius-xl: 1.25rem;
            --radius-2xl: 1.5rem;
            --shadow-glow-blue: 0 0 18px rgba(0, 212, 255, 0.45), 0 0 40px rgba(0, 212, 255, 0.18);
            --shadow-glow-purple: 0 0 18px rgba(168, 85, 247, 0.45), 0 0 40px rgba(168, 85, 247, 0.18);
            --shadow-glow-pink: 0 0 18px rgba(255, 45, 149, 0.4), 0 0 35px rgba(255, 45, 149, 0.15);
            --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.5);
            --shadow-card-hover: 0 8px 36px rgba(0, 0, 0, 0.6), 0 0 30px rgba(0, 212, 255, 0.12);
            --transition-fast: 0.2s ease;
            --transition-base: 0.3s ease;
            --transition-slow: 0.5s ease;
            --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', system-ui, -apple-system, sans-serif;
            --font-display: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
        }

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

        html {
            scroll-behavior: smooth;
            scroll-padding-top: 80px;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        body {
            font-family: var(--font-sans);
            background-color: var(--bg-primary);
            color: var(--text-primary);
            line-height: 1.7;
            min-height: 100vh;
            overflow-x: hidden;
            letter-spacing: 0.01em;
        }

        a {
            text-decoration: none;
            color: inherit;
            transition: color var(--transition-fast);
        }

        img {
            max-width: 100%;
            height: auto;
            display: block;
        }

        button {
            cursor: pointer;
            border: none;
            font-family: inherit;
            transition: all var(--transition-base);
        }

        input {
            font-family: inherit;
            outline: none;
        }

        ::selection {
            background: rgba(0, 212, 255, 0.35);
            color: #fff;
        }

        ::-webkit-scrollbar {
            width: 6px;
        }
        ::-webkit-scrollbar-track {
            background: var(--bg-primary);
        }
        ::-webkit-scrollbar-thumb {
            background: rgba(0, 212, 255, 0.3);
            border-radius: 3px;
        }
        ::-webkit-scrollbar-thumb:hover {
            background: rgba(0, 212, 255, 0.55);
        }

        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 1.5rem;
        }
        @media (max-width: 768px) {
            .container {
                padding: 0 1rem;
            }
        }

        /* ============ HEADER / NAV ============ */
        .site-header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 1000;
            background: rgba(6, 6, 15, 0.82);
            backdrop-filter: blur(22px);
            -webkit-backdrop-filter: blur(22px);
            border-bottom: 1px solid var(--border-subtle);
            transition: all var(--transition-base);
            height: 68px;
        }
        .site-header.scrolled {
            background: rgba(6, 6, 15, 0.94);
            border-bottom-color: var(--border-glow);
            box-shadow: 0 2px 28px rgba(0, 0, 0, 0.5);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 68px;
            gap: 1.5rem;
        }
        .logo-wrap {
            display: flex;
            align-items: center;
            gap: 0.6rem;
            flex-shrink: 0;
            z-index: 1001;
        }
        .logo-icon {
            width: 38px;
            height: 38px;
            border-radius: var(--radius-sm);
            background: linear-gradient(135deg, var(--neon-blue), var(--neon-purple));
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 900;
            font-size: 1.1rem;
            color: #fff;
            box-shadow: var(--shadow-glow-blue);
            letter-spacing: -0.02em;
        }
        .logo-text {
            font-size: 1.25rem;
            font-weight: 700;
            color: #fff;
            letter-spacing: 0.04em;
            white-space: nowrap;
        }
        .logo-text span {
            color: var(--neon-blue);
        }
        .nav-links {
            display: flex;
            align-items: center;
            gap: 0.25rem;
            list-style: none;
        }
        .nav-links a {
            display: inline-block;
            padding: 0.5rem 1rem;
            border-radius: var(--radius-md);
            color: var(--text-secondary);
            font-weight: 500;
            font-size: 0.95rem;
            transition: all var(--transition-fast);
            white-space: nowrap;
            position: relative;
        }
        .nav-links a:hover,
        .nav-links a:focus-visible {
            color: #fff;
            background: rgba(255, 255, 255, 0.05);
        }
        .nav-links a.nav-cta {
            background: linear-gradient(135deg, var(--neon-blue), var(--neon-purple));
            color: #fff;
            font-weight: 600;
            padding: 0.55rem 1.4rem;
            border-radius: var(--radius-lg);
            box-shadow: var(--shadow-glow-blue);
            margin-left: 0.5rem;
        }
        .nav-links a.nav-cta:hover {
            box-shadow: var(--shadow-glow-purple);
            transform: translateY(-1px);
        }
        .nav-toggle {
            display: none;
            background: none;
            border: none;
            color: #fff;
            font-size: 1.5rem;
            z-index: 1001;
            padding: 0.4rem;
            border-radius: var(--radius-sm);
            transition: all var(--transition-fast);
        }
        .nav-toggle:hover {
            background: rgba(255, 255, 255, 0.08);
        }
        @media (max-width: 900px) {
            .nav-links {
                position: fixed;
                top: 0;
                right: 0;
                width: 280px;
                height: 100vh;
                background: rgba(12, 12, 29, 0.97);
                backdrop-filter: blur(20px);
                -webkit-backdrop-filter: blur(20px);
                flex-direction: column;
                padding: 5rem 1.5rem 2rem;
                gap: 0.5rem;
                transform: translateX(100%);
                transition: transform var(--transition-base);
                border-left: 1px solid var(--border-subtle);
                z-index: 1000;
                align-items: stretch;
            }
            .nav-links.active {
                transform: translateX(0);
            }
            .nav-links a {
                padding: 0.7rem 1rem;
                font-size: 1rem;
                border-radius: var(--radius-md);
            }
            .nav-links a.nav-cta {
                margin-left: 0;
                text-align: center;
                margin-top: 0.5rem;
            }
            .nav-toggle {
                display: block;
            }
            .mobile-overlay {
                display: none;
                position: fixed;
                inset: 0;
                background: rgba(0, 0, 0, 0.55);
                z-index: 999;
            }
            .mobile-overlay.active {
                display: block;
            }
        }

        /* ============ HERO ============ */
        .hero-section {
            position: relative;
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            padding: 6rem 1.5rem 4rem;
            overflow: hidden;
            background: var(--bg-primary);
        }
        .hero-bg {
            position: absolute;
            inset: 0;
            background: url('/assets/images/backpic/back-1.webp') center / cover no-repeat;
            opacity: 0.32;
            z-index: 0;
            filter: brightness(0.7) saturate(1.4);
        }
        .hero-bg-overlay {
            position: absolute;
            inset: 0;
            background: radial-gradient(ellipse at 50% 40%, rgba(0, 180, 240, 0.12) 0%, transparent 65%),
                radial-gradient(ellipse at 30% 70%, rgba(168, 85, 247, 0.1) 0%, transparent 55%),
                linear-gradient(180deg, rgba(6, 6, 15, 0.4) 0%, rgba(6, 6, 15, 0.85) 100%);
            z-index: 1;
        }
        .hero-content {
            position: relative;
            z-index: 2;
            text-align: center;
            max-width: 820px;
        }
        .hero-badge {
            display: inline-block;
            padding: 0.35rem 1.2rem;
            border-radius: 9999px;
            background: rgba(0, 212, 255, 0.12);
            border: 1px solid rgba(0, 212, 255, 0.35);
            color: var(--neon-blue);
            font-size: 0.9rem;
            font-weight: 600;
            letter-spacing: 0.06em;
            margin-bottom: 1.5rem;
            animation: pulse-badge 3s ease-in-out infinite;
        }
        @keyframes pulse-badge {
            0%,
            100% {
                box-shadow: 0 0 8px rgba(0, 212, 255, 0.25);
            }
            50% {
                box-shadow: 0 0 22px rgba(0, 212, 255, 0.5);
            }
        }
        .hero-title {
            font-size: clamp(2.5rem, 5.5vw, 4.2rem);
            font-weight: 900;
            line-height: 1.15;
            letter-spacing: -0.02em;
            color: #fff;
            margin-bottom: 1.25rem;
        }
        .hero-title .highlight {
            background: linear-gradient(135deg, var(--neon-blue), var(--neon-cyan));
            -webkit-background-clip: text;
            background-clip: text;
            -webkit-text-fill-color: transparent;
            text-shadow: none;
            position: relative;
        }
        .hero-subtitle {
            font-size: clamp(1.05rem, 1.6vw, 1.3rem);
            color: var(--text-secondary);
            max-width: 600px;
            margin: 0 auto 2.5rem;
            line-height: 1.8;
        }
        .hero-buttons {
            display: flex;
            flex-wrap: wrap;
            gap: 1rem;
            justify-content: center;
        }
        .btn {
            display: inline-flex;
            align-items: center;
            gap: 0.5rem;
            padding: 0.8rem 2rem;
            border-radius: var(--radius-xl);
            font-weight: 600;
            font-size: 1rem;
            letter-spacing: 0.02em;
            transition: all var(--transition-base);
            white-space: nowrap;
            position: relative;
            overflow: hidden;
        }
        .btn-primary {
            background: linear-gradient(135deg, var(--neon-blue), var(--neon-purple));
            color: #fff;
            box-shadow: var(--shadow-glow-blue);
        }
        .btn-primary:hover {
            box-shadow: var(--shadow-glow-purple);
            transform: translateY(-2px);
        }
        .btn-outline {
            background: transparent;
            color: #fff;
            border: 1.5px solid rgba(255, 255, 255, 0.3);
        }
        .btn-outline:hover {
            border-color: var(--neon-blue);
            background: rgba(0, 212, 255, 0.06);
            box-shadow: 0 0 18px rgba(0, 212, 255, 0.2);
            transform: translateY(-2px);
        }
        .btn:focus-visible {
            outline: 2px solid var(--neon-blue);
            outline-offset: 3px;
        }
        .hero-stats-row {
            display: flex;
            flex-wrap: wrap;
            gap: 2rem;
            justify-content: center;
            margin-top: 3.5rem;
            padding-top: 2rem;
            border-top: 1px solid var(--border-subtle);
        }
        .hero-stat {
            text-align: center;
        }
        .hero-stat-num {
            font-size: 2rem;
            font-weight: 800;
            color: #fff;
            letter-spacing: -0.01em;
        }
        .hero-stat-num span {
            color: var(--neon-blue);
        }
        .hero-stat-label {
            font-size: 0.85rem;
            color: var(--text-muted);
            margin-top: 0.25rem;
        }

        /* ============ SECTIONS ============ */
        .section {
            padding: 5rem 0;
        }
        .section-header {
            text-align: center;
            margin-bottom: 3.5rem;
        }
        .section-label {
            display: inline-block;
            padding: 0.3rem 1rem;
            border-radius: 9999px;
            background: rgba(168, 85, 247, 0.1);
            border: 1px solid rgba(168, 85, 247, 0.3);
            color: var(--neon-purple);
            font-size: 0.85rem;
            font-weight: 600;
            letter-spacing: 0.05em;
            margin-bottom: 1rem;
        }
        .section-title {
            font-size: clamp(1.8rem, 3.5vw, 2.6rem);
            font-weight: 800;
            color: #fff;
            letter-spacing: -0.01em;
            line-height: 1.25;
        }
        .section-desc {
            color: var(--text-muted);
            font-size: 1.05rem;
            max-width: 560px;
            margin: 0.75rem auto 0;
            line-height: 1.7;
        }

        /* ============ CARDS ============ */
        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 1.5rem;
        }
        .card {
            background: var(--bg-card);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-xl);
            padding: 2rem 1.5rem;
            transition: all var(--transition-base);
            position: relative;
            overflow: hidden;
        }
        .card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 2px;
            background: linear-gradient(90deg, transparent, var(--neon-blue), transparent);
            opacity: 0;
            transition: opacity var(--transition-base);
        }
        .card:hover {
            background: var(--bg-card-hover);
            border-color: var(--border-glow);
            box-shadow: var(--shadow-card-hover);
            transform: translateY(-3px);
        }
        .card:hover::before {
            opacity: 1;
        }
        .card-icon {
            width: 52px;
            height: 52px;
            border-radius: var(--radius-md);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.5rem;
            margin-bottom: 1.25rem;
            background: rgba(0, 212, 255, 0.1);
            color: var(--neon-blue);
            border: 1px solid rgba(0, 212, 255, 0.25);
            transition: all var(--transition-base);
        }
        .card:hover .card-icon {
            box-shadow: var(--shadow-glow-blue);
            background: rgba(0, 212, 255, 0.18);
        }
        .card h3 {
            font-size: 1.2rem;
            font-weight: 700;
            color: #fff;
            margin-bottom: 0.6rem;
        }
        .card p {
            color: var(--text-muted);
            font-size: 0.95rem;
            line-height: 1.7;
        }

        /* ============ FEATURES WITH IMAGE ============ */
        .feature-row {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 3rem;
            align-items: center;
        }
        .feature-image-wrap {
            position: relative;
            border-radius: var(--radius-2xl);
            overflow: hidden;
            border: 1px solid var(--border-subtle);
            box-shadow: var(--shadow-card);
        }
        .feature-image-wrap img {
            width: 100%;
            height: auto;
            object-fit: cover;
            aspect-ratio: 4/3;
            border-radius: var(--radius-2xl);
        }
        .feature-image-glow {
            position: absolute;
            inset: -1px;
            border-radius: var(--radius-2xl);
            pointer-events: none;
            background: transparent;
            box-shadow: inset 0 0 40px rgba(0, 212, 255, 0.08);
        }
        .feature-text h3 {
            font-size: 1.6rem;
            font-weight: 800;
            color: #fff;
            margin-bottom: 1rem;
            line-height: 1.3;
        }
        .feature-text p {
            color: var(--text-secondary);
            line-height: 1.8;
            margin-bottom: 1.5rem;
        }
        .feature-list {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 0.75rem;
        }
        .feature-list li {
            display: flex;
            align-items: flex-start;
            gap: 0.6rem;
            color: var(--text-secondary);
            font-size: 0.95rem;
        }
        .feature-list li i {
            color: var(--neon-cyan);
            margin-top: 0.25rem;
            flex-shrink: 0;
        }
        @media (max-width: 768px) {
            .feature-row {
                grid-template-columns: 1fr;
                gap: 2rem;
            }
            .feature-row.reverse-mobile {
                display: flex;
                flex-direction: column-reverse;
            }
        }

        /* ============ STATS / DATA SECTION ============ */
        .stats-section {
            position: relative;
            background: url('/assets/images/backpic/back-2.webp') center / cover no-repeat;
            background-attachment: fixed;
        }
        .stats-overlay {
            position: absolute;
            inset: 0;
            background: rgba(6, 6, 15, 0.88);
            z-index: 0;
        }
        .stats-content {
            position: relative;
            z-index: 1;
        }
        .stats-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1.5rem;
            text-align: center;
        }
        .stat-card {
            background: rgba(17, 17, 40, 0.7);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-xl);
            padding: 2rem 1rem;
            transition: all var(--transition-base);
        }
        .stat-card:hover {
            border-color: var(--border-glow);
            box-shadow: var(--shadow-glow-blue);
            transform: translateY(-2px);
        }
        .stat-card .stat-num {
            font-size: 2.5rem;
            font-weight: 900;
            color: #fff;
            letter-spacing: -0.02em;
        }
        .stat-card .stat-num em {
            font-style: normal;
            color: var(--neon-blue);
        }
        .stat-card .stat-label {
            color: var(--text-muted);
            font-size: 0.9rem;
            margin-top: 0.5rem;
        }
        @media (max-width: 768px) {
            .stats-grid {
                grid-template-columns: repeat(2, 1fr);
                gap: 1rem;
            }
            .stat-card .stat-num {
                font-size: 1.8rem;
            }
        }
        @media (max-width: 480px) {
            .stats-grid {
                grid-template-columns: 1fr 1fr;
                gap: 0.75rem;
            }
        }

        /* ============ SERVICE CARDS WITH IMAGES ============ */
        .service-card {
            background: var(--bg-card);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-xl);
            overflow: hidden;
            transition: all var(--transition-base);
        }
        .service-card:hover {
            border-color: var(--border-glow);
            box-shadow: var(--shadow-card-hover);
            transform: translateY(-4px);
        }
        .service-card-img {
            width: 100%;
            aspect-ratio: 16/10;
            object-fit: cover;
            display: block;
        }
        .service-card-body {
            padding: 1.5rem;
        }
        .service-card-body h3 {
            font-size: 1.15rem;
            font-weight: 700;
            color: #fff;
            margin-bottom: 0.5rem;
        }
        .service-card-body p {
            color: var(--text-muted);
            font-size: 0.9rem;
            line-height: 1.6;
        }
        .service-tag {
            display: inline-block;
            padding: 0.2rem 0.7rem;
            border-radius: 9999px;
            font-size: 0.75rem;
            font-weight: 600;
            letter-spacing: 0.04em;
            background: rgba(0, 240, 200, 0.1);
            color: var(--neon-cyan);
            border: 1px solid rgba(0, 240, 200, 0.3);
            margin-bottom: 0.75rem;
        }

        /* ============ PROCESS / TIMELINE ============ */
        .process-list {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1.5rem;
            position: relative;
        }
        .process-item {
            text-align: center;
            position: relative;
            padding: 1.5rem 1rem;
            background: var(--bg-card);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-xl);
            transition: all var(--transition-base);
        }
        .process-item:hover {
            border-color: var(--border-purple);
            box-shadow: var(--shadow-glow-purple);
            transform: translateY(-3px);
        }
        .process-num {
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background: linear-gradient(135deg, var(--neon-purple), var(--neon-pink));
            color: #fff;
            font-weight: 900;
            font-size: 1.3rem;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 1rem;
            box-shadow: var(--shadow-glow-purple);
        }
        .process-item h4 {
            font-weight: 700;
            color: #fff;
            font-size: 1rem;
            margin-bottom: 0.4rem;
        }
        .process-item p {
            color: var(--text-muted);
            font-size: 0.85rem;
            line-height: 1.6;
        }
        @media (max-width: 900px) {
            .process-list {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        @media (max-width: 520px) {
            .process-list {
                grid-template-columns: 1fr;
                max-width: 320px;
                margin: 0 auto;
            }
        }

        /* ============ FAQ ============ */
        .faq-list {
            max-width: 760px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 0.75rem;
        }
        .faq-item {
            background: var(--bg-card);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-lg);
            overflow: hidden;
            transition: all var(--transition-base);
        }
        .faq-item.active {
            border-color: var(--border-glow);
            box-shadow: 0 0 20px rgba(0, 212, 255, 0.1);
        }
        .faq-question {
            width: 100%;
            background: none;
            color: #fff;
            font-weight: 600;
            font-size: 1rem;
            padding: 1.2rem 1.5rem;
            text-align: left;
            display: flex;
            justify-content: space-between;
            align-items: center;
            gap: 1rem;
            transition: all var(--transition-fast);
            letter-spacing: 0.01em;
        }
        .faq-question:hover {
            background: rgba(255, 255, 255, 0.02);
        }
        .faq-question i {
            transition: transform var(--transition-base);
            color: var(--neon-blue);
            flex-shrink: 0;
        }
        .faq-item.active .faq-question i {
            transform: rotate(180deg);
        }
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height var(--transition-slow), padding var(--transition-slow);
            padding: 0 1.5rem;
        }
        .faq-item.active .faq-answer {
            max-height: 300px;
            padding: 0 1.5rem 1.2rem;
        }
        .faq-answer p {
            color: var(--text-muted);
            font-size: 0.95rem;
            line-height: 1.7;
        }

        /* ============ CTA ============ */
        .cta-section {
            position: relative;
            background: url('/assets/images/backpic/back-3.webp') center / cover no-repeat;
            background-attachment: fixed;
            padding: 6rem 0;
        }
        .cta-overlay {
            position: absolute;
            inset: 0;
            background: rgba(6, 6, 15, 0.82);
            z-index: 0;
        }
        .cta-content {
            position: relative;
            z-index: 1;
            text-align: center;
            max-width: 600px;
            margin: 0 auto;
        }
        .cta-content h2 {
            font-size: clamp(1.8rem, 3.5vw, 2.5rem);
            font-weight: 900;
            color: #fff;
            margin-bottom: 1rem;
            line-height: 1.25;
        }
        .cta-content p {
            color: var(--text-secondary);
            font-size: 1.05rem;
            margin-bottom: 2rem;
            line-height: 1.7;
        }
        .cta-form {
            display: flex;
            gap: 0.75rem;
            max-width: 460px;
            margin: 0 auto;
            flex-wrap: wrap;
            justify-content: center;
        }
        .cta-form input {
            flex: 1;
            min-width: 200px;
            padding: 0.85rem 1.2rem;
            border-radius: var(--radius-xl);
            background: rgba(255, 255, 255, 0.06);
            border: 1.5px solid rgba(255, 255, 255, 0.2);
            color: #fff;
            font-size: 0.95rem;
            transition: all var(--transition-base);
        }
        .cta-form input:focus {
            border-color: var(--neon-blue);
            box-shadow: 0 0 16px rgba(0, 212, 255, 0.25);
            background: rgba(255, 255, 255, 0.1);
            outline: none;
        }
        .cta-form input::placeholder {
            color: var(--text-muted);
        }
        .cta-form .btn {
            flex-shrink: 0;
        }

        /* ============ FOOTER ============ */
        .site-footer {
            background: var(--bg-secondary);
            border-top: 1px solid var(--border-subtle);
            padding: 3rem 0 2rem;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 2.5rem;
            margin-bottom: 2.5rem;
        }
        .footer-brand p {
            color: var(--text-muted);
            font-size: 0.9rem;
            line-height: 1.7;
            margin-top: 0.75rem;
        }
        .footer-col h4 {
            color: #fff;
            font-weight: 700;
            font-size: 0.95rem;
            margin-bottom: 1rem;
            letter-spacing: 0.03em;
        }
        .footer-col ul {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 0.5rem;
        }
        .footer-col ul li a {
            color: var(--text-muted);
            font-size: 0.9rem;
            transition: color var(--transition-fast);
        }
        .footer-col ul li a:hover {
            color: var(--neon-blue);
        }
        .footer-bottom {
            border-top: 1px solid var(--border-subtle);
            padding-top: 1.5rem;
            text-align: center;
            color: var(--text-muted);
            font-size: 0.85rem;
        }
        @media (max-width: 768px) {
            .footer-grid {
                grid-template-columns: 1fr 1fr;
                gap: 2rem;
            }
            .footer-brand {
                grid-column: 1 / -1;
            }
        }
        @media (max-width: 480px) {
            .footer-grid {
                grid-template-columns: 1fr;
            }
            .footer-brand {
                grid-column: auto;
            }
        }

        /* ============ BACK TO TOP ============ */
        .back-to-top {
            position: fixed;
            bottom: 2rem;
            right: 2rem;
            width: 44px;
            height: 44px;
            border-radius: 50%;
            background: var(--bg-card);
            border: 1px solid var(--border-glow);
            color: var(--neon-blue);
            font-size: 1.1rem;
            display: flex;
            align-items: center;
            justify-content: center;
            z-index: 900;
            opacity: 0;
            pointer-events: none;
            transition: all var(--transition-base);
            box-shadow: var(--shadow-glow-blue);
        }
        .back-to-top.visible {
            opacity: 1;
            pointer-events: auto;
        }
        .back-to-top:hover {
            background: rgba(0, 212, 255, 0.15);
            transform: translateY(-3px);
            box-shadow: var(--shadow-glow-purple);
        }

        /* ============ UTILITY ============ */
        .bg-alt {
            background: var(--bg-secondary);
        }
        .text-neon {
            color: var(--neon-blue);
        }
        .text-purple {
            color: var(--neon-purple);
        }
        @media (max-width: 520px) {
            .hero-stats-row {
                gap: 1rem;
            }
            .hero-stat-num {
                font-size: 1.5rem;
            }
            .btn {
                padding: 0.7rem 1.4rem;
                font-size: 0.9rem;
            }
            .section {
                padding: 3rem 0;
            }
            .card-grid {
                grid-template-columns: 1fr;
            }
        }