:root {
            --blue-50: #eff6ff;
            --blue-100: #dbeafe;
            --blue-200: #bfdbfe;
            --blue-400: #60a5fa;
            --blue-500: #3b82f6;
            --blue-600: #2563eb;
            --blue-700: #1d4ed8;
            --blue-800: #1e40af;
            --blue-900: #1e3a5f;
            --slate-50: #f8fafc;
            --slate-100: #f1f5f9;
            --slate-200: #e2e8f0;
            --slate-300: #cbd5e1;
            --slate-400: #94a3b8;
            --slate-500: #64748b;
            --slate-600: #475569;
            --slate-700: #334155;
            --slate-800: #1e293b;
            --slate-900: #0f172a;
            --emerald-50: #ecfdf5;
            --emerald-100: #d1fae5;
            --emerald-400: #34d399;
            --emerald-500: #10b981;
            --emerald-600: #059669;
            --violet-50: #f5f3ff;
            --violet-100: #ede9fe;
            --violet-400: #a78bfa;
            --violet-500: #8b5cf6;
            --violet-600: #7c3aed;
            --amber-50: #fffbeb;
            --amber-400: #fbbf24;
            --amber-500: #f59e0b;
            --cyan-400: #22d3ee;
            --cyan-500: #06b6d4;
            --rose-400: #fb7185;
            --rose-500: #f43f5e;
            --gradient-hero: linear-gradient(160deg, #0f172a 0%, #1a2740 25%, #0d1b33 50%, #0a1628 75%, #0f172a 100%);
            --gradient-ai: linear-gradient(135deg, #7c3aed 0%, #3b82f6 50%, #06b6d4 100%);
            --gradient-edge: linear-gradient(135deg, #059669 0%, #10b981 30%, #34d399 70%, #06b6d4 100%);
            --gradient-protocol: linear-gradient(135deg, #f43f5e 0%, #f59e0b 50%, #22d3ee 100%);
            --glow-blue: 0 0 40px rgba(59, 130, 246, 0.25);
            --glow-violet: 0 0 40px rgba(124, 58, 237, 0.25);
            --glow-emerald: 0 0 40px rgba(16, 185, 129, 0.2);
            --glow-amber: 0 0 40px rgba(245, 158, 11, 0.2);
            --glow-rose: 0 0 35px rgba(244, 63, 94, 0.18);
            --radius-sm: 10px;
            --radius: 14px;
            --radius-lg: 20px;
            --radius-xl: 28px;
            --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'PingFang SC', 'Microsoft YaHei', sans-serif;
            background: #0f172a;
            color: #e2e8f0;
            line-height: 1.65;
            -webkit-font-smoothing: antialiased;
            overflow-x: hidden;
        }
        a {
            text-decoration: none;
            color: inherit;
            transition: var(--transition);
        }
        .container {
            max-width: 1240px;
            margin: 0 auto;
            padding: 0 28px;
        }

        /* ========== HEADER (与首页一致) ========== */
        .header {
            background: rgba(15, 23, 42, 0.88);
            backdrop-filter: blur(18px) saturate(140%);
            -webkit-backdrop-filter: blur(18px) saturate(140%);
            border-bottom: 1px solid rgba(255, 255, 255, 0.06);
            position: sticky;
            top: 0;
            z-index: 200;
            transition: var(--transition);
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 70px;
        }
        .logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 22px;
            font-weight: 800;
            letter-spacing: -0.3px;
            background: var(--gradient-ai);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .logo-icon {
            width: 38px;
            height: 38px;
            background: var(--gradient-ai);
            border-radius: 11px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: #fff;
            font-size: 17px;
            font-weight: 900;
            -webkit-text-fill-color: #fff;
            box-shadow: var(--glow-violet);
            position: relative;
        }
        .logo-icon::after {
            content: '';
            position: absolute;
            inset: -3px;
            border-radius: 14px;
            background: var(--gradient-ai);
            opacity: 0.35;
            z-index: -1;
            filter: blur(10px);
            animation: logoPulse 2.4s ease-in-out infinite;
        }
        @keyframes logoPulse {
            0%,
            100% {
                opacity: 0.3;
                transform: scale(1);
            }
            50% {
                opacity: 0.7;
                transform: scale(1.08);
            }
        }
        .nav {
            display: flex;
            align-items: center;
            gap: 28px;
        }
        .nav a {
            font-size: 14.5px;
            font-weight: 500;
            color: #cbd5e1;
            letter-spacing: 0.2px;
            position: relative;
            padding: 4px 0;
        }
        .nav a:hover {
            color: #ffffff;
        }
        .nav a.active {
            color: #ffffff;
            font-weight: 600;
        }
        .nav a.active::after {
            content: '';
            position: absolute;
            bottom: -3px;
            left: 0;
            right: 0;
            height: 2px;
            background: var(--gradient-ai);
            border-radius: 2px;
        }
        .nav a.nav-cta {
            background: var(--gradient-ai);
            color: #fff;
            padding: 9px 22px;
            border-radius: 22px;
            font-weight: 600;
            font-size: 13.5px;
            letter-spacing: 0.3px;
            box-shadow: var(--glow-violet);
            transition: all 0.3s;
        }
        .nav a.nav-cta:hover {
            box-shadow: 0 0 50px rgba(124, 58, 237, 0.45);
            transform: translateY(-2px);
            color: #fff;
        }
        .mobile-toggle {
            display: none;
            flex-direction: column;
            gap: 4px;
            cursor: pointer;
            padding: 6px;
            z-index: 210;
        }
        .mobile-toggle span {
            display: block;
            width: 26px;
            height: 2.5px;
            background: #e2e8f0;
            border-radius: 4px;
            transition: 0.3s;
        }
        .mobile-toggle.open span:nth-child(1) {
            transform: rotate(45deg) translate(5px, 5px);
        }
        .mobile-toggle.open span:nth-child(2) {
            opacity: 0;
        }
        .mobile-toggle.open span:nth-child(3) {
            transform: rotate(-45deg) translate(5px, -5px);
        }

        /* ========== PAGE HERO ========== */
        .page-hero {
            background: var(--gradient-hero);
            padding: 64px 0 72px;
            position: relative;
            overflow: hidden;
            border-bottom: 1px solid rgba(255, 255, 255, 0.04);
            text-align: center;
        }
        .page-hero::before {
            content: '';
            position: absolute;
            top: -35%;
            right: -10%;
            width: 600px;
            height: 600px;
            background: radial-gradient(circle, rgba(59, 130, 246, 0.1) 0%, transparent 60%);
            border-radius: 50%;
            pointer-events: none;
            animation: heroGlow 9s ease-in-out infinite;
        }
        .page-hero::after {
            content: '';
            position: absolute;
            bottom: -25%;
            left: -8%;
            width: 450px;
            height: 450px;
            background: radial-gradient(circle, rgba(124, 58, 237, 0.08) 0%, transparent 60%);
            border-radius: 50%;
            pointer-events: none;
            animation: heroGlow 11s ease-in-out infinite reverse;
        }
        @keyframes heroGlow {
            0%,
            100% {
                transform: translate(0, 0) scale(1);
            }
            33% {
                transform: translate(30px, -25px) scale(1.1);
            }
            66% {
                transform: translate(-15px, 18px) scale(0.93);
            }
        }
        .page-hero .hero-badge {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: rgba(255, 255, 255, 0.04);
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: 50px;
            padding: 6px 18px;
            font-size: 12.5px;
            font-weight: 600;
            color: #a78bfa;
            letter-spacing: 1.5px;
            text-transform: uppercase;
            margin-bottom: 20px;
            position: relative;
            z-index: 1;
            backdrop-filter: blur(8px);
        }
        .page-hero h1 {
            font-size: 44px;
            font-weight: 900;
            line-height: 1.15;
            color: #ffffff;
            margin-bottom: 16px;
            letter-spacing: -0.8px;
            position: relative;
            z-index: 1;
        }
        .page-hero h1 .gradient-text {
            background: var(--gradient-ai);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .page-hero .hero-sub {
            font-size: 16.5px;
            color: #94a3b8;
            max-width: 620px;
            margin: 0 auto 8px;
            position: relative;
            z-index: 1;
            letter-spacing: 0.15px;
        }
        .page-hero .hero-meta {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 20px;
            font-size: 13px;
            color: #64748b;
            position: relative;
            z-index: 1;
            margin-top: 12px;
            flex-wrap: wrap;
        }
        .page-hero .hero-meta span {
            display: inline-flex;
            align-items: center;
            gap: 5px;
        }
        .page-hero .hero-meta .dot-sep {
            width: 4px;
            height: 4px;
            background: #475569;
            border-radius: 50%;
        }

        /* ========== SECTION COMMON ========== */
        .section {
            padding: 72px 0;
            position: relative;
        }
        .section-dark {
            background: #0a0f1a;
        }
        .section-alt {
            background: #0f172a;
        }
        .section-header {
            text-align: center;
            max-width: 680px;
            margin: 0 auto 48px;
        }
        .section-header .tag {
            display: inline-block;
            font-size: 11.5px;
            font-weight: 700;
            letter-spacing: 2.5px;
            text-transform: uppercase;
            color: #a78bfa;
            margin-bottom: 10px;
        }
        .section-header h2 {
            font-size: 34px;
            font-weight: 900;
            color: #ffffff;
            margin-bottom: 12px;
            letter-spacing: -0.5px;
        }
        .section-header h2 .gradient-text {
            background: var(--gradient-ai);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .section-header p {
            font-size: 15.5px;
            color: #94a3b8;
        }

        /* ========== 四层架构可视化 (核心创意版块) ========== */
        .architecture-stack {
            display: flex;
            flex-direction: column;
            gap: 0;
            max-width: 800px;
            margin: 0 auto;
            position: relative;
        }
        .arch-layer {
            background: rgba(255, 255, 255, 0.02);
            border: 1px solid rgba(255, 255, 255, 0.06);
            border-radius: var(--radius-lg);
            padding: 28px 32px;
            position: relative;
            transition: all 0.35s;
            cursor: default;
            z-index: 1;
        }
        .arch-layer:hover {
            transform: translateX(8px);
            z-index: 5;
        }
        .arch-layer.layer-l4 {
            background: rgba(124, 58, 237, 0.06);
            border-color: rgba(124, 58, 237, 0.2);
            margin-top: 0;
        }
        .arch-layer.layer-l4:hover {
            border-color: rgba(124, 58, 237, 0.5);
            box-shadow: var(--glow-violet);
            background: rgba(124, 58, 237, 0.1);
        }
        .arch-layer.layer-l3 {
            background: rgba(59, 130, 246, 0.05);
            border-color: rgba(59, 130, 246, 0.18);
            margin-top: -8px;
        }
        .arch-layer.layer-l3:hover {
            border-color: rgba(59, 130, 246, 0.5);
            box-shadow: var(--glow-blue);
            background: rgba(59, 130, 246, 0.09);
        }
        .arch-layer.layer-l2 {
            background: rgba(6, 182, 212, 0.05);
            border-color: rgba(6, 182, 212, 0.18);
            margin-top: -8px;
        }
        .arch-layer.layer-l2:hover {
            border-color: rgba(6, 182, 212, 0.5);
            box-shadow: 0 0 40px rgba(6, 182, 212, 0.2);
            background: rgba(6, 182, 212, 0.09);
        }
        .arch-layer.layer-l1 {
            background: rgba(16, 185, 129, 0.05);
            border-color: rgba(16, 185, 129, 0.2);
            margin-top: -8px;
        }
        .arch-layer.layer-l1:hover {
            border-color: rgba(16, 185, 129, 0.5);
            box-shadow: var(--glow-emerald);
            background: rgba(16, 185, 129, 0.09);
        }
        .arch-layer .layer-badge {
            display: inline-block;
            font-size: 10px;
            font-weight: 800;
            letter-spacing: 1.5px;
            text-transform: uppercase;
            padding: 4px 12px;
            border-radius: 20px;
            margin-bottom: 10px;
        }
        .layer-l4 .layer-badge {
            background: rgba(124, 58, 237, 0.2);
            color: #c4b5fd;
        }
        .layer-l3 .layer-badge {
            background: rgba(59, 130, 246, 0.2);
            color: #93c5fd;
        }
        .layer-l2 .layer-badge {
            background: rgba(6, 182, 212, 0.2);
            color: #67e8f9;
        }
        .layer-l1 .layer-badge {
            background: rgba(16, 185, 129, 0.2);
            color: #6ee7b7;
        }
        .arch-layer .layer-title {
            font-size: 20px;
            font-weight: 800;
            color: #ffffff;
            margin-bottom: 4px;
            letter-spacing: -0.3px;
        }
        .arch-layer .layer-desc {
            font-size: 13.5px;
            color: #94a3b8;
            line-height: 1.5;
        }
        .arch-layer .layer-tech-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
            margin-top: 10px;
        }
        .arch-layer .layer-tech-tags span {
            font-size: 11px;
            padding: 3px 10px;
            border-radius: 12px;
            background: rgba(255, 255, 255, 0.04);
            border: 1px solid rgba(255, 255, 255, 0.1);
            color: #cbd5e1;
            letter-spacing: 0.2px;
        }
        .arch-arrow {
            display: flex;
            align-items: center;
            justify-content: center;
            height: 28px;
            position: relative;
            z-index: 2;
            margin: -4px 0;
        }
        .arch-arrow svg {
            width: 24px;
            height: 24px;
            opacity: 0.5;
        }
        .arch-arrow .arrow-line {
            stroke: #475569;
            stroke-width: 2;
        }
        .arch-flow-indicator {
            position: absolute;
            right: -60px;
            top: 50%;
            transform: translateY(-50%);
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 4px;
            font-size: 10px;
            color: #64748b;
            letter-spacing: 0.8px;
            pointer-events: none;
        }
        @media (max-width: 900px) {
            .arch-flow-indicator {
                display: none;
            }
            .arch-layer {
                padding: 20px 18px;
            }
            .arch-layer .layer-title {
                font-size: 17px;
            }
        }

        /* ========== 协议深度解析卡片 ========== */
        .protocol-deep-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 32px;
            align-items: start;
        }
        .protocol-code-block {
            background: #070b14;
            border: 1px solid rgba(255, 255, 255, 0.08);
            border-radius: var(--radius-lg);
            padding: 28px 24px;
            font-family: 'SF Mono', 'Fira Code', 'Consolas', 'Monaco', monospace;
            font-size: 13px;
            line-height: 1.8;
            color: #cbd5e1;
            position: relative;
            overflow: hidden;
            letter-spacing: 0.1px;
        }
        .protocol-code-block::before {
            content: '● ● ●';
            position: absolute;
            top: 12px;
            left: 16px;
            color: #475569;
            font-size: 10px;
            letter-spacing: 4px;
        }
        .protocol-code-block .code-keyword {
            color: #c4b5fd;
        }
        .protocol-code-block .code-string {
            color: #6ee7b7;
        }
        .protocol-code-block .code-comment {
            color: #64748b;
            font-style: italic;
        }
        .protocol-code-block .code-func {
            color: #93c5fd;
        }
        .protocol-code-block .code-num {
            color: #fbbf24;
        }
        .protocol-insight {
            display: flex;
            flex-direction: column;
            gap: 14px;
        }
        .protocol-insight h3 {
            font-size: 22px;
            font-weight: 800;
            color: #fff;
            letter-spacing: -0.4px;
        }
        .protocol-insight p {
            font-size: 14.5px;
            color: #94a3b8;
        }
        .protocol-insight .insight-stat {
            display: flex;
            gap: 20px;
            flex-wrap: wrap;
        }
        .protocol-insight .insight-stat .insight-num {
            font-size: 32px;
            font-weight: 900;
            background: var(--gradient-protocol);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .protocol-insight .insight-stat .insight-label {
            font-size: 12px;
            color: #64748b;
        }

        /* ========== 架构演进时间线 ========== */
        .timeline {
            position: relative;
            max-width: 800px;
            margin: 0 auto;
            padding-left: 40px;
        }
        .timeline::before {
            content: '';
            position: absolute;
            left: 18px;
            top: 0;
            bottom: 0;
            width: 2px;
            background: linear-gradient(to bottom, #7c3aed, #3b82f6, #06b6d4, #10b981);
            border-radius: 2px;
            opacity: 0.5;
        }
        .timeline-item {
            position: relative;
            margin-bottom: 36px;
            padding-left: 28px;
        }
        .timeline-item::before {
            content: '';
            position: absolute;
            left: -26px;
            top: 6px;
            width: 14px;
            height: 14px;
            border-radius: 50%;
            background: #0f172a;
            border: 3px solid #a78bfa;
            box-shadow: 0 0 16px rgba(124, 58, 237, 0.35);
            z-index: 2;
        }
        .timeline-item:nth-child(2)::before {
            border-color: #3b82f6;
            box-shadow: 0 0 16px rgba(59, 130, 246, 0.35);
        }
        .timeline-item:nth-child(3)::before {
            border-color: #06b6d4;
            box-shadow: 0 0 16px rgba(6, 182, 212, 0.35);
        }
        .timeline-item:nth-child(4)::before {
            border-color: #10b981;
            box-shadow: 0 0 16px rgba(16, 185, 129, 0.35);
        }
        .timeline-item .tl-date {
            font-size: 12px;
            font-weight: 700;
            letter-spacing: 1.5px;
            color: #a78bfa;
            margin-bottom: 4px;
        }
        .timeline-item .tl-title {
            font-size: 18px;
            font-weight: 800;
            color: #ffffff;
            margin-bottom: 4px;
            letter-spacing: -0.2px;
        }
        .timeline-item .tl-desc {
            font-size: 13.5px;
            color: #94a3b8;
        }

        /* ========== 专利矩阵 ========== */
        .patent-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 20px;
        }
        .patent-card {
            background: rgba(255, 255, 255, 0.02);
            border: 1px solid rgba(255, 255, 255, 0.06);
            border-radius: var(--radius);
            padding: 22px 20px;
            transition: all 0.3s;
            position: relative;
        }
        .patent-card:hover {
            border-color: rgba(167, 139, 250, 0.35);
            box-shadow: var(--glow-violet);
            transform: translateY(-4px);
        }
        .patent-card .patent-id {
            font-size: 10px;
            font-weight: 700;
            letter-spacing: 1.5px;
            color: #a78bfa;
            margin-bottom: 6px;
        }
        .patent-card .patent-title {
            font-size: 15px;
            font-weight: 700;
            color: #ffffff;
            margin-bottom: 4px;
        }
        .patent-card .patent-desc {
            font-size: 12.5px;
            color: #64748b;
        }
        .patent-card .patent-status {
            display: inline-block;
            margin-top: 8px;
            font-size: 10px;
            padding: 3px 10px;
            border-radius: 10px;
            background: rgba(16, 185, 129, 0.15);
            color: #34d399;
            font-weight: 600;
            letter-spacing: 0.5px;
        }

        /* ========== 可用率仪表盘 ========== */
        .availability-showcase {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 40px;
            align-items: center;
        }
        .avail-ring-container {
            display: flex;
            justify-content: center;
            align-items: center;
            position: relative;
        }
        .avail-ring {
            width: 220px;
            height: 220px;
            border-radius: 50%;
            position: relative;
            display: flex;
            align-items: center;
            justify-content: center;
            background: conic-gradient(#10b981 0deg 359.64deg, rgba(255, 255, 255, 0.04) 359.64deg 360deg);
            box-shadow: 0 0 60px rgba(16, 185, 129, 0.25), inset 0 0 40px rgba(16, 185, 129, 0.05);
        }
        .avail-ring::before {
            content: '';
            position: absolute;
            inset: 16px;
            border-radius: 50%;
            background: #0a0f1a;
            border: 1px solid rgba(255, 255, 255, 0.06);
        }
        .avail-ring-inner {
            position: relative;
            z-index: 2;
            text-align: center;
        }
        .avail-ring-inner .avail-num {
            font-size: 52px;
            font-weight: 900;
            color: #ffffff;
            letter-spacing: -2px;
            line-height: 1;
        }
        .avail-ring-inner .avail-label {
            font-size: 13px;
            color: #34d399;
            letter-spacing: 0.5px;
            font-weight: 600;
            margin-top: 2px;
        }
        .avail-details {
            display: flex;
            flex-direction: column;
            gap: 18px;
        }
        .avail-details h3 {
            font-size: 24px;
            font-weight: 800;
            color: #fff;
            letter-spacing: -0.4px;
        }
        .avail-details p {
            font-size: 14.5px;
            color: #94a3b8;
        }
        .avail-metrics-row {
            display: flex;
            gap: 16px;
            flex-wrap: wrap;
        }
        .avail-metric-mini {
            background: rgba(255, 255, 255, 0.02);
            border: 1px solid rgba(255, 255, 255, 0.06);
            border-radius: var(--radius-sm);
            padding: 14px 16px;
            text-align: center;
            min-width: 80px;
            flex: 1;
        }
        .avail-metric-mini .mini-num {
            font-size: 20px;
            font-weight: 800;
            color: #fff;
        }
        .avail-metric-mini .mini-label {
            font-size: 10px;
            color: #64748b;
            letter-spacing: 0.5px;
        }

        /* ========== CTA ========== */
        .cta-section {
            background: #0a0f1a;
            border-top: 1px solid rgba(255, 255, 255, 0.04);
        }
        .cta-box {
            background: rgba(255, 255, 255, 0.02);
            border-radius: var(--radius-xl);
            padding: 52px 44px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 24px;
            border: 1px solid rgba(255, 255, 255, 0.06);
            position: relative;
            overflow: hidden;
        }
        .cta-box::after {
            content: '';
            position: absolute;
            top: -55%;
            right: -18%;
            width: 380px;
            height: 380px;
            background: radial-gradient(circle, rgba(124, 58, 237, 0.08) 0%, transparent 60%);
            pointer-events: none;
        }
        .cta-box .cta-text h2 {
            font-size: 28px;
            font-weight: 900;
            color: #ffffff;
            margin-bottom: 6px;
            letter-spacing: -0.4px;
            position: relative;
            z-index: 1;
        }
        .cta-box .cta-text p {
            font-size: 15px;
            color: #94a3b8;
            position: relative;
            z-index: 1;
        }
        .cta-box .cta-btn {
            position: relative;
            z-index: 1;
        }
        .btn-primary {
            display: inline-flex;
            align-items: center;
            gap: 9px;
            background: var(--gradient-ai);
            color: #fff;
            padding: 14px 34px;
            border-radius: 28px;
            font-size: 15.5px;
            font-weight: 700;
            letter-spacing: 0.3px;
            transition: all 0.3s;
            box-shadow: var(--glow-violet);
            position: relative;
            overflow: hidden;
        }
        .btn-primary::before {
            content: '';
            position: absolute;
            inset: 0;
            background: linear-gradient(135deg, rgba(255, 255, 255, 0.2) 0%, transparent 60%);
            pointer-events: none;
        }
        .btn-primary:hover {
            box-shadow: 0 0 55px rgba(124, 58, 237, 0.5);
            transform: translateY(-3px);
            color: #fff;
        }

        /* ========== FOOTER (与首页一致) ========== */
        .footer {
            background: #070b14;
            color: #94a3b8;
            padding: 52px 0 28px;
            border-top: 1px solid rgba(255, 255, 255, 0.04);
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 40px;
            margin-bottom: 32px;
        }
        .footer-brand .logo {
            margin-bottom: 12px;
            font-size: 20px;
        }
        .footer-brand .logo .logo-icon {
            background: var(--gradient-ai);
            -webkit-text-fill-color: #fff;
        }
        .footer-brand p {
            font-size: 13.5px;
            max-width: 280px;
            color: #64748b;
            line-height: 1.7;
        }
        .footer-col h4 {
            font-size: 14px;
            font-weight: 700;
            color: #e2e8f0;
            margin-bottom: 14px;
            letter-spacing: 0.3px;
        }
        .footer-col ul {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 8px;
        }
        .footer-col ul a {
            font-size: 13.5px;
            color: #64748b;
            transition: var(--transition);
        }
        .footer-col ul a:hover {
            color: #cbd5e1;
        }
        .footer-bottom {
            border-top: 1px solid rgba(255, 255, 255, 0.05);
            padding-top: 20px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 12px;
            font-size: 12.5px;
            color: #475569;
        }
        .footer-bottom .links {
            display: flex;
            gap: 18px;
        }
        .footer-bottom .links a {
            color: #475569;
            transition: var(--transition);
            font-size: 12.5px;
        }
        .footer-bottom .links a:hover {
            color: #94a3b8;
        }

        /* ========== RESPONSIVE ========== */
        @media (max-width: 1024px) {
            .protocol-deep-grid,
            .availability-showcase {
                grid-template-columns: 1fr;
                text-align: center;
            }
            .protocol-insight .insight-stat {
                justify-content: center;
            }
            .avail-ring-container {
                order: -1;
            }
            .avail-metrics-row {
                justify-content: center;
            }
            .patent-grid {
                grid-template-columns: 1fr 1fr;
            }
            .footer-grid {
                grid-template-columns: 1fr 1fr;
            }
            .page-hero h1 {
                font-size: 34px;
            }
            .architecture-stack {
                max-width: 100%;
            }
            .timeline {
                padding-left: 30px;
            }
            .timeline::before {
                left: 12px;
            }
            .timeline-item {
                padding-left: 22px;
            }
            .timeline-item::before {
                left: -20px;
                width: 12px;
                height: 12px;
            }
        }
        @media (max-width: 768px) {
            .nav {
                display: none;
                flex-direction: column;
                position: absolute;
                top: 70px;
                left: 0;
                right: 0;
                background: rgba(15, 23, 42, 0.96);
                backdrop-filter: blur(20px);
                padding: 20px 24px;
                gap: 14px;
                border-bottom: 1px solid rgba(255, 255, 255, 0.08);
                box-shadow: 0 16px 40px rgba(0, 0, 0, 0.5);
                z-index: 190;
            }
            .nav.open {
                display: flex;
            }
            .nav a.nav-cta {
                width: 100%;
                text-align: center;
            }
            .mobile-toggle {
                display: flex;
            }
            .page-hero h1 {
                font-size: 28px;
            }
            .page-hero {
                padding: 44px 0 50px;
            }
            .section {
                padding: 48px 0;
            }
            .section-header h2 {
                font-size: 26px;
            }
            .patent-grid {
                grid-template-columns: 1fr;
            }
            .cta-box {
                padding: 32px 20px;
                flex-direction: column;
                text-align: center;
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 28px;
            }
            .footer-bottom {
                flex-direction: column;
                text-align: center;
            }
            .arch-layer {
                padding: 18px 14px;
            }
            .arch-layer .layer-title {
                font-size: 16px;
            }
            .arch-layer .layer-tech-tags span {
                font-size: 10px;
                padding: 2px 8px;
            }
            .avail-ring {
                width: 160px;
                height: 160px;
            }
            .avail-ring-inner .avail-num {
                font-size: 36px;
            }
            .protocol-code-block {
                font-size: 11px;
                padding: 20px 14px;
            }
            .timeline {
                padding-left: 22px;
            }
            .timeline::before {
                left: 8px;
            }
            .timeline-item {
                padding-left: 18px;
                margin-bottom: 24px;
            }
            .timeline-item::before {
                left: -16px;
                width: 10px;
                height: 10px;
            }
            .timeline-item .tl-title {
                font-size: 15px;
            }
        }
        @media (max-width: 480px) {
            .page-hero h1 {
                font-size: 24px;
            }
            .page-hero .hero-sub {
                font-size: 14px;
            }
            .section-header h2 {
                font-size: 22px;
            }
            .avail-metrics-row {
                flex-direction: column;
                align-items: center;
            }
            .avail-metric-mini {
                width: 100%;
                max-width: 200px;
            }
            .btn-primary {
                padding: 12px 22px;
                font-size: 14px;
            }
            .protocol-insight .insight-num {
                font-size: 24px;
            }
        }