/* roulang page: index */
:root {
            --bg-obsidian: #0B0F17;
            --bg-titanium: #131B2B;
            --bg-surface: rgba(30, 41, 59, 0.7);
            --bg-card: rgba(19, 27, 43, 0.85);
            --accent-emerald: #10B981;
            --accent-cyan: #06B6D4;
            --accent-amber: #F59E0B;
            --text-pure: #F8FAFC;
            --text-body: #94A3B8;
            --text-dim: #64748B;
            --border-subtle: rgba(148, 163, 184, 0.14);
            --border-glow: rgba(16, 185, 129, 0.35);
            --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
            --radius-sm: 4px;
            --radius-md: 6px;
            --radius-lg: 12px;
            --font-main: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
            --font-code: "JetBrains Mono", Consolas, Monaco, "Courier New", monospace;
        }

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

        html {
            scroll-behavior: smooth;
        }

        body {
            background-color: var(--bg-obsidian);
            color: var(--text-body);
            font-family: var(--font-main);
            font-size: 16px;
            line-height: 1.75;
            overflow-x: hidden;
            -webkit-font-smoothing: antialiased;
        }

        a {
            color: inherit;
            text-decoration: none;
            transition: all 0.25s ease;
        }

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

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

        /* 统一双行导航 */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 1000;
            background: rgba(11, 15, 23, 0.92);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border-subtle);
        }

        .utility-bar {
            background: rgba(6, 11, 20, 0.95);
            border-bottom: 1px solid rgba(148, 163, 184, 0.08);
            font-size: 12px;
            color: var(--text-dim);
            padding: 6px 0;
        }

        .utility-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .status-badge {
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }

        .status-dot {
            width: 7px;
            height: 7px;
            background: var(--accent-emerald);
            border-radius: 50%;
            box-shadow: 0 0 8px var(--accent-emerald);
            animation: pulse-dot 2s infinite ease-in-out;
        }

        @keyframes pulse-dot {
            0%, 100% { opacity: 1; transform: scale(1); }
            50% { opacity: 0.4; transform: scale(0.85); }
        }

        .main-navbar {
            padding: 16px 0;
        }

        .nav-wrapper {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .brand-logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 20px;
            font-weight: 700;
            color: var(--text-pure);
            letter-spacing: -0.5px;
        }

        .brand-logo .logo-icon {
            width: 32px;
            height: 32px;
            background: linear-gradient(135deg, var(--accent-emerald), var(--accent-cyan));
            border-radius: var(--radius-sm);
            display: flex;
            align-items: center;
            justify-content: center;
            color: #06090e;
            font-weight: 900;
            font-size: 16px;
        }

        .nav-links {
            display: flex;
            align-items: center;
            gap: 28px;
            list-style: none;
        }

        .nav-links a {
            color: var(--text-body);
            font-size: 14px;
            font-weight: 500;
            position: relative;
            padding: 6px 0;
        }

        .nav-links a:hover,
        .nav-links a.active {
            color: var(--text-pure);
        }

        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 2px;
            background: linear-gradient(90deg, var(--accent-emerald), var(--accent-cyan));
            transition: width 0.25s ease;
        }

        .nav-links a:hover::after {
            width: 100%;
        }

        .nav-actions {
            display: flex;
            align-items: center;
            gap: 14px;
        }

        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            padding: 10px 20px;
            border-radius: var(--radius-md);
            font-size: 14px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.25s ease;
            border: 1px solid transparent;
        }

        .btn-primary {
            background: linear-gradient(135deg, var(--accent-emerald), #059669);
            color: #04130d;
            box-shadow: 0 4px 14px rgba(16, 185, 129, 0.25);
        }

        .btn-primary:hover {
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(16, 185, 129, 0.4);
            filter: brightness(1.08);
        }

        .btn-secondary {
            background: rgba(30, 41, 59, 0.6);
            color: var(--text-pure);
            border-color: var(--border-subtle);
        }

        .btn-secondary:hover {
            background: rgba(51, 65, 85, 0.8);
            border-color: rgba(148, 163, 184, 0.3);
            transform: translateY(-2px);
        }

        .menu-toggle {
            display: none;
            background: none;
            border: none;
            color: var(--text-pure);
            font-size: 24px;
            cursor: pointer;
        }

        /* 通用板块样式 */
        .section {
            padding: 88px 0;
            position: relative;
        }

        .section-alt {
            background-color: var(--bg-titanium);
            border-top: 1px solid var(--border-subtle);
            border-bottom: 1px solid var(--border-subtle);
        }

        .section-header {
            text-align: center;
            max-width: 800px;
            margin: 0 auto 56px auto;
        }

        .section-tag {
            display: inline-block;
            font-size: 12px;
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 1px;
            color: var(--accent-emerald);
            background: rgba(16, 185, 129, 0.1);
            border: 1px solid rgba(16, 185, 129, 0.25);
            padding: 4px 12px;
            border-radius: var(--radius-sm);
            margin-bottom: 14px;
        }

        .section-title {
            font-size: 32px;
            font-weight: 700;
            color: var(--text-pure);
            line-height: 1.3;
            margin-bottom: 16px;
        }

        .section-desc {
            font-size: 16px;
            color: var(--text-body);
            line-height: 1.7;
        }

        /* 1. Hero 舞台居中与价值点 */
        .hero-section {
            padding: 72px 0 96px 0;
            background: radial-gradient(circle at 50% 20%, rgba(16, 185, 129, 0.08) 0%, rgba(11, 15, 23, 1) 70%),
                        linear-gradient(180deg, var(--bg-obsidian) 0%, var(--bg-titanium) 100%);
            border-bottom: 1px solid var(--border-subtle);
            position: relative;
            overflow: hidden;
        }

        .hero-content {
            text-align: center;
            max-width: 900px;
            margin: 0 auto 40px auto;
        }

        .hero-telemetry {
            display: inline-flex;
            align-items: center;
            gap: 12px;
            padding: 6px 16px;
            background: rgba(30, 41, 59, 0.5);
            border: 1px solid var(--border-subtle);
            border-radius: 20px;
            font-family: var(--font-code);
            font-size: 13px;
            color: var(--accent-cyan);
            margin-bottom: 24px;
        }

        .hero-title {
            font-size: 44px;
            font-weight: 800;
            color: var(--text-pure);
            line-height: 1.25;
            margin-bottom: 20px;
            letter-spacing: -0.5px;
        }

        .hero-title span {
            background: linear-gradient(135deg, #F8FAFC 20%, var(--accent-emerald) 80%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }

        .hero-intro {
            font-size: 17px;
            line-height: 1.8;
            color: var(--text-body);
            margin-bottom: 32px;
        }

        .hero-actions {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 16px;
            margin-bottom: 48px;
        }...center;
                    justify-content: space-between;
                    margin-top: 20px;
                }

                .hero-action {
                    padding: 10px 20px;
                    border-radius: 5px;
                    text-decoration: none;
                    color: white;
                    font-weight: bold;
                    transition: background-color 0.2s ease;
                }

                .hero-action:hover {
                    opacity: 0.8;
                }

                .hero-cta {
                    background-color: #007bff;
                }

                .hero-secondary {
                    background-color: #6c757d;
                }

                .features {
                    padding: 50px 0;
                    text-align: center;
                }

                .features-grid {
                    display: grid;
                    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
                    gap: 30px;
                    margin-top: 30px;
                }

                .feature {
                    padding: 20px;
                    border: 1px solid #ddd;
                    border-radius: 5px;
                }

                .feature h3 {
                    margin-bottom: 10px;
                }

                .feature p {
                    color: #555;
                }

                .footer {
                    background-color: #343a40;
                    color: white;
                    text-align: center;
                    padding: 20px 0;
                }