:root {
            --bg: #ffffff;
            --surface: #f8fafc;
            --surface-alt: #f1f5f9;
            --text: #0f172a;
            --text-secondary: #475569;
            --text-muted: #64748b;
            --accent: #2563eb;
            --accent-light: #3b82f6;
            --accent-glow: rgba(37, 99, 235, 0.08);
            --border: #e2e8f0;
            --border-light: #f1f5f9;
            --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.04);
            --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.06);
            --shadow-lg: 0 20px 48px rgba(0, 0, 0, 0.08);
            --shadow-xl: 0 32px 64px rgba(0, 0, 0, 0.1);
            --radius-sm: 12px;
            --radius: 20px;
            --radius-lg: 28px;
            --radius-xl: 36px;
            --transition: 0.28s cubic-bezier(0.4, 0, 0.2, 1);
            --font-sans: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
            --gradient-hero: linear-gradient(135deg, #2563eb 0%, #06b6d4 50%, #3b82f6 100%);
            --gradient-cta: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #0f172a 100%);
            --gradient-card: linear-gradient(160deg, #ffffff 0%, #f8fafc 100%);
            --color-protocol-trojan: #7c3aed;
            --color-protocol-vless: #2563eb;
            --color-protocol-wg: #f59e0b;
            --color-protocol-ss: #10b981;
        }

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

        html {
            scroll-behavior: smooth;
            -webkit-text-size-adjust: 100%;
            text-size-adjust: 100%;
        }

        body {
            font-family: var(--font-sans);
            background: var(--bg);
            color: var(--text);
            line-height: 1.6;
            overflow-x: hidden;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
            text-rendering: optimizeLegibility;
        }

        .sr-only {
            position: absolute;
            width: 1px;
            height: 1px;
            padding: 0;
            margin: -1px;
            overflow: hidden;
            clip: rect(0, 0, 0, 0);
            border: 0;
        }

        .container {
            max-width: 1220px;
            margin: 0 auto;
            padding: 0 28px;
        }

        /* HEADER */
        header {
            background: rgba(255, 255, 255, 0.88);
            backdrop-filter: blur(18px);
            -webkit-backdrop-filter: blur(18px);
            position: sticky;
            top: 0;
            z-index: 1000;
            border-bottom: 1px solid rgba(0, 0, 0, 0.04);
            transition: var(--transition);
        }
        header.scrolled {
            box-shadow: var(--shadow-md);
            background: rgba(255, 255, 255, 0.95);
        }

        nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 16px 0;
            flex-wrap: wrap;
            gap: 14px;
        }

        .logo {
            font-size: 1.75rem;
            font-weight: 800;
            letter-spacing: -0.025em;
            background: var(--gradient-hero);
            -webkit-background-clip: text;
            background-clip: text;
            -webkit-text-fill-color: transparent;
            flex-shrink: 0;
            white-space: nowrap;
        }

        .nav-links {
            display: flex;
            gap: 28px;
            align-items: center;
            flex-wrap: wrap;
            list-style: none;
        }
        .nav-links a {
            text-decoration: none;
            font-weight: 500;
            color: var(--text-secondary);
            transition: var(--transition);
            font-size: 0.95rem;
            position: relative;
            padding: 4px 0;
            white-space: nowrap;
        }
        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: -2px;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--accent);
            border-radius: 2px;
            transition: width var(--transition);
        }
        .nav-links a:hover {
            color: var(--accent);
        }
        .nav-links a:hover::after {
            width: 100%;
        }
        .nav-links a.active {
            color: var(--accent);
            font-weight: 600;
        }
        .nav-links a.active::after {
            width: 100%;
        }

        /* PAGE HERO */
        .page-hero {
            padding: 72px 0 56px;
            background: radial-gradient(ellipse at 80% 5%, rgba(37, 99, 235, 0.04) 0%, #ffffff 55%),
                radial-gradient(ellipse at 20% 90%, rgba(6, 182, 212, 0.03) 0%, #ffffff 55%);
            text-align: center;
        }
        .page-hero .badge {
            background: #eef2ff;
            color: #1e40af;
            display: inline-flex;
            align-items: center;
            gap: 6px;
            padding: 7px 18px;
            border-radius: 40px;
            font-size: 0.82rem;
            font-weight: 600;
            margin-bottom: 16px;
            letter-spacing: 0.01em;
            border: 1px solid rgba(37, 99, 235, 0.12);
        }
        .page-hero h1 {
            font-size: clamp(2rem, 4vw, 3rem);
            font-weight: 800;
            letter-spacing: -0.025em;
            margin-bottom: 16px;
            color: #0a0c10;
            line-height: 1.2;
        }
        .page-hero .hero-gradient-text {
            background: var(--gradient-hero);
            -webkit-background-clip: text;
            background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .page-hero .subtitle {
            font-size: 1.05rem;
            color: var(--text-secondary);
            max-width: 680px;
            margin: 0 auto 8px;
            line-height: 1.5;
        }

        /* SECTION TITLES */
        .section-title-v2 {
            text-align: center;
            font-size: clamp(1.6rem, 3vw, 2rem);
            font-weight: 700;
            margin-bottom: 12px;
            color: var(--text);
            letter-spacing: -0.02em;
        }
        .section-subtitle {
            text-align: center;
            color: var(--text-muted);
            font-size: 0.95rem;
            margin-bottom: 44px;
            max-width: 620px;
            margin-left: auto;
            margin-right: auto;
            line-height: 1.5;
        }

        /* PROTOCOL CARDS */
        .protocols-section {
            padding: 70px 0;
            background: var(--surface);
        }
        .protocol-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 20px;
        }
        .protocol-card {
            background: #ffffff;
            border-radius: var(--radius-lg);
            padding: 28px 20px;
            text-align: center;
            border: 1px solid var(--border-light);
            box-shadow: var(--shadow-sm);
            transition: var(--transition);
            position: relative;
            overflow: hidden;
        }
        .protocol-card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-lg);
            border-color: rgba(37, 99, 235, 0.15);
        }
        .protocol-card .proto-icon {
            font-size: 2.6rem;
            margin-bottom: 12px;
            display: block;
        }
        .protocol-card h3 {
            font-size: 1.2rem;
            font-weight: 700;
            margin-bottom: 6px;
            color: var(--text);
        }
        .protocol-card .proto-tag {
            display: inline-block;
            padding: 4px 12px;
            border-radius: 20px;
            font-size: 0.75rem;
            font-weight: 600;
            margin-bottom: 8px;
            background: #f1f5f9;
            color: var(--text-secondary);
        }
        .protocol-card p {
            font-size: 0.85rem;
            color: var(--text-muted);
            line-height: 1.5;
        }
        .protocol-card .proto-color-bar {
            height: 4px;
            width: 100%;
            position: absolute;
            top: 0;
            left: 0;
            border-radius: 0 0 4px 4px;
            opacity: 0.3;
        }
        .proto-trojan .proto-color-bar { background: var(--color-protocol-trojan); }
        .proto-vless .proto-color-bar { background: var(--color-protocol-vless); }
        .proto-wireguard .proto-color-bar { background: var(--color-protocol-wg); }
        .proto-shadowsocks .proto-color-bar { background: var(--color-protocol-ss); }

        /* RULES CORE */
        .rules-core {
            padding: 70px 0;
            background: #ffffff;
        }
        .rules-showcase {
            display: flex;
            gap: 40px;
            flex-wrap: wrap;
            align-items: center;
        }
        .rules-text {
            flex: 1;
            min-width: 280px;
        }
        .rules-text h2 {
            font-size: clamp(1.5rem, 2.5vw, 1.9rem);
            font-weight: 700;
            margin-bottom: 16px;
            color: var(--text);
        }
        .rules-text p {
            color: var(--text-secondary);
            margin-bottom: 12px;
            line-height: 1.6;
        }
        .rule-type-list {
            list-style: none;
            margin-top: 16px;
        }
        .rule-type-list li {
            display: flex;
            align-items: baseline;
            gap: 10px;
            margin-bottom: 10px;
            font-size: 0.9rem;
            color: var(--text-secondary);
        }
        .rule-type-list .rule-badge {
            background: #eef2ff;
            color: #1e40af;
            padding: 3px 10px;
            border-radius: 14px;
            font-weight: 600;
            font-size: 0.78rem;
            white-space: nowrap;
            flex-shrink: 0;
        }
        .rules-diagram {
            flex: 1;
            min-width: 280px;
            background: #f8fafc;
            border-radius: var(--radius-xl);
            padding: 28px 24px;
            box-shadow: var(--shadow-md);
            border: 1px solid var(--border-light);
        }
        .diagram-step {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-bottom: 14px;
            font-size: 0.9rem;
        }
        .diagram-step .step-icon {
            width: 38px;
            height: 38px;
            border-radius: 50%;
            background: #ffffff;
            border: 2px solid var(--border);
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            flex-shrink: 0;
            color: var(--accent);
            box-shadow: var(--shadow-sm);
        }
        .diagram-arrow {
            text-align: center;
            color: var(--accent);
            font-size: 1.2rem;
            margin: 4px 0 4px 19px;
            font-weight: 700;
        }

        /* DNS & LOGGING */
        .dns-logs-section {
            padding: 70px 0;
            background: var(--surface);
        }
        .two-col {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 28px;
        }
        .info-card {
            background: #ffffff;
            border-radius: var(--radius-lg);
            padding: 28px 24px;
            border: 1px solid var(--border-light);
            box-shadow: var(--shadow-sm);
            transition: var(--transition);
        }
        .info-card:hover {
            box-shadow: var(--shadow-lg);
            border-color: rgba(37, 99, 235, 0.12);
            transform: translateY(-4px);
        }
        .info-card .card-header {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-bottom: 14px;
        }
        .info-card .card-header .icon {
            font-size: 2rem;
        }
        .info-card h3 {
            font-size: 1.25rem;
            font-weight: 700;
            color: var(--text);
        }
        .info-card p {
            font-size: 0.9rem;
            color: var(--text-muted);
            line-height: 1.6;
            margin-bottom: 10px;
        }
        .info-card ul {
            list-style: none;
            margin-top: 8px;
        }
        .info-card ul li {
            font-size: 0.85rem;
            color: var(--text-secondary);
            margin-bottom: 6px;
            padding-left: 18px;
            position: relative;
        }
        .info-card ul li::before {
            content: '•';
            color: var(--accent);
            font-weight: 700;
            position: absolute;
            left: 4px;
        }

        /* APP-LEVEL PROXY */
        .app-proxy-section {
            padding: 70px 0;
            background: #ffffff;
        }
        .app-proxy-grid {
            display: flex;
            gap: 36px;
            flex-wrap: wrap;
            align-items: center;
        }
        .app-proxy-text {
            flex: 1;
            min-width: 260px;
        }
        .app-proxy-text h2 {
            font-size: clamp(1.5rem, 2.5vw, 1.9rem);
            font-weight: 700;
            margin-bottom: 16px;
            color: var(--text);
        }
        .app-proxy-text p {
            color: var(--text-secondary);
            line-height: 1.6;
            margin-bottom: 12px;
        }
        .feature-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
            margin-top: 16px;
        }
        .feature-tag {
            background: #eef2ff;
            color: #1e40af;
            padding: 6px 16px;
            border-radius: 30px;
            font-size: 0.82rem;
            font-weight: 600;
            border: 1px solid rgba(37, 99, 235, 0.15);
        }
        .app-proxy-visual {
            flex: 1;
            min-width: 260px;
            background: #f8fafc;
            border-radius: var(--radius-xl);
            padding: 32px 24px;
            text-align: center;
            box-shadow: var(--shadow-md);
            border: 1px solid var(--border-light);
        }
        .app-proxy-visual .app-list {
            display: flex;
            flex-wrap: wrap;
            gap: 12px;
            justify-content: center;
        }
        .app-item {
            background: #ffffff;
            border-radius: 16px;
            padding: 10px 16px;
            box-shadow: var(--shadow-sm);
            border: 1px solid #f1f5f9;
            font-size: 0.85rem;
            font-weight: 500;
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .app-item .app-dot {
            width: 8px;
            height: 8px;
            border-radius: 50%;
            background: var(--accent);
            display: inline-block;
        }

        /* ADVANCED FEATURES */
        .advanced-section {
            padding: 70px 0;
            background: var(--surface);
        }
        .advanced-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 20px;
        }
        .advanced-card {
            background: #ffffff;
            border-radius: var(--radius-lg);
            padding: 26px 20px;
            text-align: center;
            border: 1px solid var(--border-light);
            box-shadow: var(--shadow-sm);
            transition: var(--transition);
        }
        .advanced-card:hover {
            transform: translateY(-5px);
            box-shadow: var(--shadow-lg);
            border-color: rgba(37, 99, 235, 0.15);
        }
        .advanced-card .adv-icon {
            font-size: 2.4rem;
            margin-bottom: 12px;
        }
        .advanced-card h4 {
            font-size: 1.1rem;
            margin-bottom: 6px;
            color: var(--text);
        }
        .advanced-card p {
            font-size: 0.85rem;
            color: var(--text-muted);
        }

        /* QUICK LINKS */
        .quick-links-section {
            padding: 56px 0;
            background: #ffffff;
        }
        .quick-links-grid {
            display: flex;
            flex-wrap: wrap;
            gap: 14px;
            justify-content: center;
        }
        .quick-link-card {
            background: #ffffff;
            border-radius: var(--radius);
            padding: 18px 22px;
            border: 1px solid var(--border-light);
            text-decoration: none;
            color: var(--text);
            font-weight: 600;
            font-size: 0.9rem;
            transition: var(--transition);
            display: flex;
            align-items: center;
            gap: 8px;
            box-shadow: var(--shadow-sm);
            flex: 1;
            min-width: 170px;
            max-width: 220px;
            justify-content: center;
        }
        .quick-link-card:hover {
            border-color: var(--accent);
            color: var(--accent);
            box-shadow: var(--shadow-lg);
            transform: translateY(-3px);
        }

        /* CTA */
        .cta-v2 {
            background: var(--gradient-cta);
            color: #ffffff;
            padding: 64px 0;
            text-align: center;
            position: relative;
            overflow: hidden;
        }
        .cta-v2::before {
            content: '';
            position: absolute;
            top: -40%;
            left: -20%;
            width: 140%;
            height: 180%;
            background: radial-gradient(ellipse at center, rgba(37, 99, 235, 0.2) 0%, transparent 70%);
            pointer-events: none;
        }
        .cta-v2 h2 {
            font-size: clamp(1.4rem, 2.5vw, 1.8rem);
            position: relative;
            z-index: 1;
        }
        .cta-v2 p {
            margin: 12px auto 0;
            max-width: 500px;
            opacity: 0.85;
            position: relative;
            z-index: 1;
            font-size: 0.9rem;
            line-height: 1.5;
        }
        .btn-cta-light {
            background: #ffffff;
            color: #0f172a;
            padding: 14px 42px;
            border-radius: 60px;
            font-weight: 700;
            text-decoration: none;
            display: inline-block;
            margin-top: 24px;
            transition: var(--transition);
            position: relative;
            z-index: 1;
            font-size: 0.95rem;
        }
        .btn-cta-light:hover {
            background: #e2e8f0;
            transform: scale(1.03);
            box-shadow: 0 10px 28px rgba(255, 255, 255, 0.2);
        }
        .cta-extra {
            margin-top: 20px;
            font-size: 0.78rem;
            opacity: 0.7;
            position: relative;
            z-index: 1;
        }

        /* FOOTER */
        footer {
            background: #020617;
            color: #94a3b8;
            padding: 52px 0 28px;
        }
        .footer-grid {
            display: flex;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 36px;
            margin-bottom: 40px;
        }
        .footer-grid>div {
            min-width: 150px;
        }
        .footer-grid h4 {
            color: #ffffff;
            font-size: 0.95rem;
            margin-bottom: 8px;
        }
        .footer-grid ul {
            list-style: none;
        }
        .footer-grid ul li {
            margin-bottom: 6px;
        }
        .footer-grid a {
            color: #94a3b8;
            text-decoration: none;
            font-size: 0.85rem;
            transition: var(--transition);
        }
        .footer-grid a:hover {
            color: #ffffff;
        }
        .footer-bottom {
            border-top: 1px solid #1e293b;
            padding-top: 24px;
            text-align: center;
            font-size: 0.78rem;
            color: #64748b;
        }

        @media (max-width: 900px) {
            .page-hero h1 {
                font-size: 1.7rem;
            }
            .rules-showcase {
                flex-direction: column;
            }
            .app-proxy-grid {
                flex-direction: column;
            }
            .nav-links {
                gap: 14px;
            }
            .nav-links a {
                font-size: 0.82rem;
            }
            .container {
                padding: 0 16px;
            }
        }
        @media (max-width: 600px) {
            nav {
                flex-direction: column;
                align-items: flex-start;
                gap: 10px;
            }
        }