/* roulang page: index */
:root {
            --primary-dark: #0D151C;
            --brand-green: #00FF9D;
            --brand-emerald: #10B981;
            --surface-slate: #1E293B;
            --surface-elevated: #15222E;
            --bg-light: #F8FAFC;
            --bg-alt: #EFF4F9;
            --border-dim: rgba(255, 255, 255, 0.08);
            --border-light: rgba(13, 21, 28, 0.08);
            --text-white: #FFFFFF;
            --text-bright: #F1F5F9;
            --text-muted: #94A3B8;
            --text-dark: #0F172A;
            --text-dark-muted: #475569;
            --amber-alert: #F59E0B;
            --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, sans-serif;
            --font-mono: "JetBrains Mono", "Fira Code", monospace;
            --radius-sm: 4px;
            --radius-md: 6px;
            --shadow-subtle: 0 4px 20px -2px rgba(13, 21, 28, 0.05);
            --shadow-card: 0 10px 25px -5px rgba(0, 0, 0, 0.2);
            --transition-smooth: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
        }

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

        html {
            font-size: 16px;
            scroll-behavior: smooth;
        }

        body {
            font-family: var(--font-sans);
            background-color: var(--primary-dark);
            color: var(--text-bright);
            line-height: 1.75;
            -webkit-font-smoothing: antialiased;
            overflow-x: hidden;
        }

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

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

        .container {
            width: 100%;
            max-width: 1240px;
            margin: 0 auto;
            padding: 0 24px;
        }

        /* Top Bar */
        .utility-bar {
            background-color: #080D11;
            border-bottom: 1px solid var(--border-dim);
            font-size: 13px;
            color: var(--text-muted);
            padding: 8px 0;
        }
        .utility-flex {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .utility-meta {
            display: flex;
            gap: 20px;
            font-family: var(--font-mono);
        }
        .utility-status {
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }
        .status-dot {
            width: 7px;
            height: 7px;
            background-color: var(--brand-green);
            border-radius: 50%;
            box-shadow: 0 0 8px var(--brand-green);
        }

        /* Main Navigation */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 1000;
            background: rgba(13, 21, 28, 0.95);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border-dim);
        }
        .nav-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 72px;
        }
        .brand-logo {
            display: flex;
            align-items: center;
            gap: 12px;
            font-size: 20px;
            font-weight: 700;
            color: var(--text-white);
            letter-spacing: -0.5px;
        }
        .brand-badge {
            background: rgba(0, 255, 157, 0.12);
            color: var(--brand-green);
            border: 1px solid rgba(0, 255, 157, 0.3);
            font-size: 11px;
            padding: 2px 6px;
            border-radius: var(--radius-sm);
            font-family: var(--font-mono);
        }
        .nav-links {
            display: flex;
            gap: 28px;
            list-style: none;
        }
        .nav-links a {
            font-size: 15px;
            color: var(--text-muted);
            font-weight: 500;
            position: relative;
            padding: 4px 0;
        }
        .nav-links a:hover, .nav-links a.active {
            color: var(--brand-green);
        }
        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--brand-green);
            transition: width 0.2s ease;
        }
        .nav-links a:hover::after, .nav-links a.active::after {
            width: 100%;
        }
        .nav-actions {
            display: flex;
            align-items: center;
            gap: 16px;
        }

        /* Buttons */
        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            padding: 11px 22px;
            border-radius: var(--radius-sm);
            font-size: 14px;
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition-smooth);
            min-height: 44px;
            border: 1px solid transparent;
            font-family: var(--font-sans);
        }
        .btn-brand {
            background-color: var(--brand-green);
            color: #051610;
        }
        .btn-brand:hover {
            background-color: #33ffb1;
            transform: translateY(-1px);
            box-shadow: 0 4px 16px rgba(0, 255, 157, 0.3);
        }
        .btn-outline {
            background-color: transparent;
            border-color: rgba(255, 255, 255, 0.2);
            color: var(--text-white);
        }
        .btn-outline:hover {
            border-color: var(--brand-green);
            color: var(--brand-green);
            background: rgba(0, 255, 157, 0.05);
        }
        .btn-sm {
            padding: 8px 16px;
            font-size: 13px;
            min-height: 36px;
        }

        /* Mobile Hamburger */
        .nav-toggle {
            display: none;
            background: none;
            border: none;
            color: var(--text-white);
            font-size: 24px;
            cursor: pointer;
            padding: 8px;
        }

        /* Hero Stack Layout */
        .hero-section {
            padding: 80px 0 100px;
            background: radial-gradient(circle at 50% 20%, rgba(16, 185, 129, 0.08) 0%, rgba(13, 21, 28, 1) 70%), url('/assets/images/491579962e895443.webp') center/cover no-repeat;
            position: relative;
            border-bottom: 1px solid var(--border-dim);
        }
        .hero-intro {
            text-align: center;
            max-width: 860px;
            margin: 0 auto 56px;
        }
        .hero-tag {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 6px 14px;
            background: rgba(0, 255, 157, 0.08);
            border: 1px solid rgba(0, 255, 157, 0.25);
            border-radius: 20px;
            color: var(--brand-green);
            font-size: 13px;
            font-weight: 500;
            margin-bottom: 24px;
        }
        .hero-title {
            font-size: clamp(34px, 4.2vw, 50px);
            font-weight: 800;
            line-height: 1.25;
            letter-spacing: -0.02em;
            color: var(--text-white);
            margin-bottom: 24px;
        }
        .hero-desc {
            font-size: 16px;
            color: var(--text-muted);
            line-height: 1.8;
            max-width: 780px;
            margin: 0 auto 32px;
        }
        .hero-cta-group {
            display: flex;
            justify-content: center;
            gap: 16px;
        }

        /* Hero Stack Cards */
        .hero-stack-container {
            display: grid;
            grid-template-columns: 1fr 1.35fr 1fr;
            align-items: center;
            gap: 20px;
            margin-top: 40px;
        }
        .stack-card {
            background: var(--surface-slate);
            border: 1px solid var(--border-dim);
            border-radius: var(--radius-md);
            padding: 24px;
            box-shadow: var(--shadow-card);
            transition: var(--transition-smooth);
        }
        .stack-card.side-card {
            opacity: 0.88;
            transform: scale(0.96);
        }
        .stack-card.main-card {
            border-color: rgba(0, 255, 157, 0.4);
            background: var(--surface-elevated);
            transform: scale(1.02);
            position: relative;
            z-index: 2;
        }
        .stack-card:hover {
            opacity: 1;
            transform: translateY(-4px);
            border-color: var(--brand-green);
        }
        .card-subtext {
            font-size: 12px;
            font-family: var(--font-mono);
            color: var(--brand-green);
            margin-bottom: 8px;
            text-transform: uppercase;
        }
        .stack-title {
            font-size: 18px;
            font-weight: 700;
            margin-bottom: 12px;
            color: var(--text-white);
        }
        .stack-body {
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.6;
        }
        .metric-badge {
            margin-top: 16px;
            padding-top: 14px;
            border-top: 1px solid var(--border-dim);
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-family: var(--font-mono);
            font-size: 13px;
        }
        .metric-val {
            color: var(--brand-green);
            font-weight: 700;
        }

        /* Universal Section Styles */
        section {
            padding: 88px 0;
            position: relative;
        }
        .section-light {
            background-color: var(--bg-light);
            color: var(--text-dark);
            border-top: 1px solid var(--border-light);
            border-bottom: 1px solid var(--border-light);
        }
        .section-dark-alt {
            background-color: #0A1016;
            border-top: 1px solid var(--border-dim);
            border-bottom: 1px solid var(--border-dim);
        }
        .section-header {
            max-width: 820px;
            margin: 0 auto 56px;
            text-align: center;
        }
        .section-subtitle {
            font-size: 13px;
            font-family: var(--font-mono);
            color: var(--brand-emerald);
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: 1px;
            margin-bottom: 12px;
        }
        .section-title {
            font-size: clamp(26px, 2.8vw, 36px);
            font-weight: 700;
            line-height: 1.3;
            letter-spacing: -0.01em;
            margin-bottom: 16px;
        }
        .section-desc {
            font-size: 15px;
            line-height: 1.75;
            color: inherit;
            opacity: 0.8;
        }
        .section-light .section-desc {
            color: var(--text-dark-muted);
            opacity: 1;
        }

        /* Grid Framework */
        .grid-2 {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 32px;
            align-items: center;
        }
        .grid-3 {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 28px;
        }
        .grid-4 {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
        }

        /* Card Component */
        .feature-card {
            background: var(--surface-slate);
            border: 1px solid var(--border-dim);
            border-radius: var(--radius-md);
            padding: 30px 24px;
            transition: var(--transition-smooth);
            position: relative;
        }
        .section-light .feature-card {
            background: #FFFFFF;
            border: 1px solid var(--border-light);
            box-shadow: var(--shadow-subtle);
        }
        .feature-card:hover {
            transform: translateY(-4px);
            border-color: var(--brand-green);
        }
        .section-light .feature-card:hover {
            border-color: var(--brand-emerald);
            box-shadow: 0 10px 30px rgba(0,0,0,0.08);
        }
        .card-icon-wrap {
            width: 48px;
            height: 48px;
            border-radius: var(--radius-sm);
            background: rgba(0, 255, 157, 0.1);
            color: var(--brand-green);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 20px;
            margin-bottom: 20px;
            font-family: var(--font-mono);
            font-weight: bold;
        }
        .section-light .card-icon-wrap {
            background: rgba(16, 185, 129, 0.1);
            color: var(--brand-emerald);
        }
        .card-h3 {
            font-size: 18px;
            font-weight: 700;
            margin-bottom: 12px;
            color: var(--text-white);
        }
        .section-light .card-h3 {
            color: var(--text-dark);
        }
        .card-p {
            font-size: 14px;
            line-height: 1.7;
            color: var(--text-muted);
        }
        .section-light .card-p {
            color: var(--text-dark-muted);
        }

        /* Matrix Product Cards */
        .product-tier-card {
            background: var(--surface-slate);
            border: 1px solid var(--border-dim);
            border-radius: var(--radius-md);
            padding: 36px 28px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
            position: relative;
        }
        .product-tier-card.featured {
            border-color: var(--brand-green);
            background: var(--surface-elevated);
        }
        .tier-tag {
            position: absolute;
            top: -12px;
            right: 24px;
            background: var(--brand-green);
            color: #000;
            font-size: 11px;
            font-weight: 700;
            padding: 2px 10px;
            border-radius: 12px;
            text-transform: uppercase;
        }
        .tier-title {
            font-size: 22px;
            font-weight: 700;
            margin-bottom: 10px;
            color: var(--text-white);
        }
        .tier-spec-list {
            list-style: none;
            margin: 24px 0 32px;
            display: flex;
            flex-direction: column;
            gap: 12px;
        }
        .tier-spec-item {
            font-size: 14px;
            color: var(--text-muted);
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .tier-spec-item::before {
            content: "✓";
            color: var(--brand-green);
            font-weight: bold;
        }

        /* Benchmark Dual Comparison */
        .comparison-table-wrap {
            overflow-x: auto;
            border: 1px solid var(--border-dim);
            border-radius: var(--radius-md);
            background: var(--surface-slate);
        }
        .comp-table {
            width: 100%;
            border-collapse: collapse;
            text-align: left;
            font-size: 14px;
        }
        .comp-table th, .comp-table td {
            padding: 18px 24px;
            border-bottom: 1px solid var(--border-dim);
        }
        .comp-table th {
            background: #15222E;
            color: var(--text-white);
            font-weight: 600;
        }
        .comp-table td {
            color: var(--text-muted);
        }
        .comp-highlight {
            color: var(--brand-green) !important;
            font-weight: 600;
            font-family: var(--font-mono);
        }

        /* Milestones Timeline */
        .timeline {
            position: relative;
            max-width: 900px;
            margin: 0 auto;
        }
        .timeline::after {
            content: '';
            position: absolute;
            width: 2px;
            background: var(--border-dim);
            top: 0;
            bottom: 0;
            left: 50%;
            margin-left: -1px;
        }
        .timeline-item {
            padding: 10px 40px;
            position: relative;
            width: 50%;
        }
        .timeline-item.left {
            left: 0;
            text-align: right;
        }
        .timeline-item.right {
            left: 50%;
            text-align: left;
        }
        .timeline-item::after {
            content: '';
            position: absolute;
            width: 14px;
            height: 14px;
            right: -7px;
            background-color: var(--brand-green);
            border: 3px solid var(--primary-dark);
            top: 18px;
            border-radius: 50%;
            z-index: 1;
        }
        .timeline-item.right::after {
            left: -7px;
        }
        .timeline-content {
            padding: 20px 24px;
            background: var(--surface-slate);
            border: 1px solid var(--border-dim);
            border-radius: var(--radius-md);
        }
        .timeline-year {
            font-family: var(--font-mono);
            color: var(--brand-green);
            font-size: 13px;
            font-weight: 700;
            margin-bottom: 6px;
        }
        .timeline-title {
            font-size: 16px;
            font-weight: 700;
            color: var(--text-white);
            margin-bottom: 8px;
        }
        .timeline-p {
            font-size: 13px;
            color: var(--text-muted);
            line-height: 1.6;
        }

        /* Stats Bar */
        .stats-section {
            background: #090E13;
            border-top: 1px solid var(--border-dim);
            border-bottom: 1px solid var(--border-dim);
            padding: 56px 0;
        }
        .stat-box {
            text-align: center;
            padding: 0 16px;
            border-right: 1px solid var(--border-dim);
        }
        .stat-box:last-child {
            border-right: none;
        }
        .stat-number {
            font-size: 38px;
            font-weight: 800;
            font-family: var(--font-mono);
            color: var(--brand-green);
            line-height: 1.1;
            margin-bottom: 8px;
        }
        .stat-label {
            font-size: 14px;
            color: var(--text-muted);
        }

        /* Stories & Quotes */
        .story-card {
            background: var(--surface-slate);
            border: 1px solid var(--border-dim);
            border-radius: var(--radius-md);
            overflow: hidden;
            display: flex;
            flex-direction: column;
        }
        .story-img {
            width: 100%;
            height: 200px;
            object-fit: cover;
            border-bottom: 1px solid var(--border-dim);
        }
        .story-content {
            padding: 24px;
            display: flex;
            flex-direction: column;
            flex-grow: 1;
        }
        .story-tag {
            font-size: 12px;
            font-family: var(--font-mono);
            color: var(--brand-emerald);
            margin-bottom: 8px;
        }
        .story-title {
            font-size: 18px;
            font-weight: 700;
            color: var(--text-white);
            margin-bottom: 12px;
        }
        .story-p {
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.6;
            margin-bottom: 16px;
            flex-grow: 1;
        }
        .story-footer {
            font-size: 13px;
            color: #64748B;
            border-top: 1px solid var(--border-dim);
            padding-top: 12px;
        }

        /* FAQ Accordion (Clean CSS details) */
        .faq-wrap {
            max-width: 860px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }
        details.faq-item {
            background: var(--surface-slate);
            border: 1px solid var(--border-dim);
            border-radius: var(--radius-md);
            overflow: hidden;
            transition: var(--transition-smooth);
        }
        details.faq-item[open] {
            border-color: rgba(0, 255, 157, 0.4);
        }
        summary.faq-q {
            padding: 20px 24px;
            font-size: 16px;
            font-weight: 600;
            color: var(--text-white);
            cursor: pointer;
            list-style: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
            user-select: none;
        }
        summary.faq-q::-webkit-details-marker {
            display: none;
        }
        summary.faq-q::after {
            content: "+";
            font-size: 20px;
            color: var(--brand-green);
            font-family: var(--font-mono);
            transition: transform 0.2s ease;
        }
        details.faq-item[open] summary.faq-q::after {
            transform: rotate(45deg);
        }
        .faq-a {
            padding: 0 24px 20px;
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.75;
            border-top: 1px solid var(--border-dim);
            padding-top: 16px;
        }

        /* Form Card */
        .form-container {
            max-width: 760px;
            margin: 0 auto;
            background: var(--surface-elevated);
            border: 1px solid rgba(0, 255, 157, 0.2);
            border-radius: var(--radius-md);
            padding: 44px;
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
        }
        .form-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 20px;
            margin-bottom: 20px;
        }
        .form-group {
            display: flex;
            flex-direction: column;
            gap: 8px;
        }
        .form-group.full {
            grid-column: span 2;
        }
        .form-label {
            font-size: 13px;
            font-weight: 500;
            color: var(--text-white);
        }
        .form-input, .form-select, .form-textarea {
            width: 100%;
            background: #0D151C;
            border: 1px solid var(--border-dim);
            border-radius: var(--radius-sm);
            padding: 12px 16px;
            color: var(--text-white);
            font-size: 14px;
            font-family: var(--font-sans);
            outline: none;
            transition: var(--transition-smooth);
        }
        .form-input:focus, .form-select:focus, .form-textarea:focus {
            border-color: var(--brand-green);
            box-shadow: 0 0 0 2px rgba(0, 255, 157, 0.15);
        }
        .form-notice {
            font-size: 12px;
            color: var(--text-muted);
            margin-top: 12px;
            text-align: center;
        }

        /* Footer */
        .site-footer {
            background-color: #070B0E;
            border-top: 1px solid var(--border-dim);
            padding: 72px 0 36px;
            font-size: 14px;
            color: var(--text-muted);
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
            gap: 40px;
            margin-bottom: 60px;
        }
        .footer-logo {
            font-size: 18px;
            font-weight: 700;
            color: var(--text-white);
            margin-bottom: 16px;
            display: inline-block;
        }
        .footer-desc {
            font-size: 13px;
            line-height: 1.7;
            color: #64748B;
            margin-bottom: 20px;
        }
        .footer-heading {
            font-size: 14px;
            font-weight: 600;
            color: var(--text-white);
            margin-bottom: 20px;
            letter-spacing: 0.5px;
        }
        .footer-links {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 12px;
        }
        .footer-links a:hover {
            color: var(--brand-green);
        }
        .footer-contact-info {
            display: flex;
            flex-direction: column;
            gap: 10px;
            font-size: 13px;
        }
        .footer-bottom {
            padding-top: 32px;
            border-top: 1px solid var(--border-dim);
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 12px;
            color: #475569;
            flex-wrap: wrap;
            gap: 16px;
        }
        .footer-icp {
            color: #475569;
        }
        .footer-icp:hover {
            color: var(--text-muted);
        }

        /* Responsive Breakpoints */
        @media (max-width: 1024px) {
            .hero-stack-container {
                grid-template-columns: 1fr;
                max-width: 600px;
                margin: 40px auto 0;
            }
            .stack-card.side-card {
                transform: none;
                opacity: 1;
            }
            .stack-card.main-card {
                transform: none;
            }
            .grid-4 {
                grid-template-columns: repeat(2, 1fr);
            }
            .timeline::after {
                left: 31px;
            }
            .timeline-item {
                width: 100%;
                padding-left: 70px;
                padding-right: 25px;
            }
            .timeline-item.left, .timeline-item.right {
                left: 0;
                text-align: left;
            }
            .timeline-item.left::after, .timeline-item.right::after {
                left: 24px;
            }
            .footer-grid {
                grid-template-columns: 1fr 1fr;
            }
        }

        @media (max-width: 768px) {
            .utility-bar {
                display: none;
            }
            .nav-links {
                display: none;
                position: absolute;
                top: 72px;
                left: 0;
                right: 0;
                background: #0D151C;
                flex-direction: column;
                padding: 24px;
                border-bottom: 1px solid var(--border-dim);
                gap: 18px;
            }
            .nav-links.is-open {
                display: flex;
            }
            .nav-toggle {
                display: block;
            }
            .grid-2, .grid-3 {
                grid-template-columns: 1fr;
            }
            .stats-section .grid-4 {
                grid-template-columns: 1fr 1fr;
                gap: 24px;
            }
            .stat-box {
                border-right: none;
                border-bottom: 1px solid var(--border-dim);
                padding-bottom: 20px;
            }
            .form-grid {
                grid-template-columns: 1fr;
            }
            .form-group.full {
                grid-column: span 1;
            }
            .form-container {
                padding: 24px;
            }
            .footer-grid {
                grid-template-columns: 1fr;
            }
            .hero-cta-group {
                flex-direction: column;
            }
            .hero-cta-group .btn {
                width: 100%;
            }
        }