:root {
            --color-primary: #2563eb;
            --color-primary-deep: #1d4ed8;
            --color-primary-light: #60a5fa;
            --color-accent: #0d9488;
            --color-accent-warm: #f97316;
            --color-accent-soft: #fbbf24;
            --color-surface: #f8fafc;
            --color-surface-alt: #f1f5f9;
            --color-card: #ffffff;
            --color-text: #1e293b;
            --color-text-muted: #475569;
            --color-text-light: #64748b;
            --color-border: #e2e8f0;
            --color-border-hover: #cbd5e1;
            --color-shadow: rgba(30, 64, 175, 0.06);
            --color-shadow-hover: rgba(37, 99, 235, 0.14);
            --color-footer-bg: #0f172a;
            --color-footer-text: #cbd5e1;
            --color-tag-bg: #eff6ff;
            --color-tag-text: #1d4ed8;
            --color-success: #10b981;
            --gradient-hero: linear-gradient(135deg, #1e40af 0%, #2563eb 28%, #0d9488 62%, #0891b2 100%);
            --gradient-btn: linear-gradient(135deg, #2563eb, #0d9488);
            --gradient-btn-hover: linear-gradient(135deg, #1d4ed8, #0f766e);
            --radius-sm: 8px;
            --radius-md: 14px;
            --radius-lg: 20px;
            --radius-full: 50px;
            --transition: 0.2s ease;
        }
        * { margin: 0; padding: 0; box-sizing: border-box; }
        body {
            font-family: system-ui, -apple-system, 'Segoe UI', 'Roboto', 'Helvetica Neue', 'Noto Sans SC', sans-serif;
            background: var(--color-surface);
            color: var(--color-text);
            line-height: 1.6;
            scroll-behavior: smooth;
            -webkit-font-smoothing: antialiased;
            font-display: swap;
        }
        .container { max-width: 1240px; margin: 0 auto; padding: 0 20px; }
        /* 导航（与首页一致） */
        .header {
            background: rgba(255,255,255,0.95); backdrop-filter: blur(10px); -webkit-backdrop-filter: blur(10px);
            box-shadow: 0 1px 3px var(--color-shadow); position: sticky; top: 0; z-index: 50;
            border-bottom: 1px solid var(--color-border);
        }
        .navbar { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; padding: 12px 0; gap: 12px; }
        .logo {
            font-size: 1.55rem; font-weight: 750; background: var(--gradient-hero); background-clip: text;
            -webkit-background-clip: text; color: transparent; letter-spacing: -0.02em; text-decoration: none; white-space: nowrap;
        }
        .nav-links { display: flex; gap: 18px; align-items: center; flex-wrap: wrap; list-style: none; }
        .nav-links a {
            text-decoration: none; font-weight: 520; color: #334155; transition: color var(--transition);
            font-size: 0.9rem; white-space: nowrap; position: relative; padding: 4px 0;
        }
        .nav-links a::after {
            content: ''; position: absolute; bottom: -2px; left: 0; width: 0; height: 2px;
            background: var(--color-primary); border-radius: 2px; transition: width var(--transition);
        }
        .nav-links a:hover::after, .nav-links a.active::after { width: 100%; }
        .nav-links a:hover, .nav-links a.active { color: var(--color-primary); }
        .nav-links .btn-nav-cta {
            background: var(--gradient-btn); color: #fff !important; padding: 7px 18px; border-radius: var(--radius-full);
            font-weight: 600; transition: all var(--transition); font-size: 0.85rem; letter-spacing: 0.02em;
        }
        .nav-links .btn-nav-cta::after { display: none; }
        .nav-links .btn-nav-cta:hover { background: var(--gradient-btn-hover); transform: translateY(-1px); box-shadow: 0 4px 14px -4px rgba(37,99,235,0.4); }
        .nav-toggle { display: none; background: none; border: none; font-size: 1.5rem; cursor: pointer; color: var(--color-text); padding: 4px 8px; }
        @media (max-width: 860px) {
            .nav-links { display: none; flex-direction: column; width: 100%; gap: 6px; padding-top: 8px; }
            .nav-links.open { display: flex; }
            .nav-toggle { display: block; }
            .nav-links a { padding: 8px 4px; font-size: 0.88rem; width: 100%; }
            .nav-links .btn-nav-cta { text-align: center; margin-top: 4px; }
        }
        /* 页面Hero */
        .page-hero {
            padding: 56px 0 32px; text-align: center;
            background: linear-gradient(170deg, #f8fafc 0%, #eff6ff 35%, #f0fdfa 70%, #fff 100%);
        }
        .page-hero h1 {
            font-size: clamp(1.8rem, 4.5vw, 2.4rem); font-weight: 800; background: var(--gradient-hero);
            background-clip: text; -webkit-background-clip: text; color: transparent; margin-bottom: 10px; letter-spacing: -0.02em;
        }
        .page-hero .sub { color: var(--color-text-muted); font-size: 1rem; max-width: 620px; margin: 0 auto 16px; }
        /* 公用 */
        .section-title { text-align: center; font-size: 1.5rem; font-weight: 720; margin-bottom: 6px; }
        .section-desc { text-align: center; color: var(--color-text-muted); margin-bottom: 26px; font-size: 0.9rem; }
        .badge {
            display: inline-block; padding: 2px 8px; border-radius: 10px; font-size: 0.65rem; font-weight: 700;
            letter-spacing: 0.03em; vertical-align: middle; margin-left: 4px;
        }
        .badge-hot { background: #fee2e2; color: #991b1b; }
        .badge-rec { background: #dcfce7; color: #166534; }
        .badge-adv { background: #ede9fe; color: #5b21b6; }
        .badge-info { background: #dbeafe; color: #1e40af; }
        /* 节点类型网格 */
        .node-type-grid {
            display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 16px;
            max-width: 1000px; margin: 0 auto;
        }
        .node-card {
            background: var(--color-card); border: 1px solid var(--color-border); border-radius: var(--radius-md);
            padding: 18px 14px; transition: all var(--transition);
        }
        .node-card:hover { border-color: var(--color-primary-light); box-shadow: 0 6px 18px -4px var(--color-shadow-hover); transform: translateY(-2px); }
        .node-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: 6px; display: flex; align-items: center; gap: 4px; }
        .node-card p { font-size: 0.82rem; color: var(--color-text-muted); line-height: 1.5; }
        .node-stat { display: flex; gap: 10px; margin-top: 8px; font-size: 0.72rem; color: var(--color-text-light); }
        .node-stat span { background: #f1f5f9; padding: 2px 8px; border-radius: 10px; }
        /* 订阅系统区 */
        .subscribe-flow {
            display: flex; flex-wrap: wrap; justify-content: center; align-items: center; gap: 12px;
            margin: 20px 0 30px;
        }
        .flow-step {
            background: var(--color-card); border: 1px solid var(--color-border); border-radius: var(--radius-md);
            padding: 14px 16px; text-align: center; min-width: 130px; flex: 1 1 130px;
        }
        .flow-step .flow-num { font-weight: 800; color: var(--color-primary); font-size: 1rem; }
        .flow-step .flow-title { font-weight: 600; font-size: 0.85rem; margin: 4px 0; }
        .flow-step .flow-desc { font-size: 0.72rem; color: var(--color-text-muted); }
        .flow-arrow { font-size: 1.2rem; color: #94a3b8; flex-shrink: 0; }
        /* 测速方法双栏 */
        .grid-2col { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; max-width: 900px; margin: 0 auto; }
        .info-card {
            background: var(--color-card); border: 1px solid var(--color-border); border-radius: var(--radius-md);
            padding: 18px; transition: all var(--transition);
        }
        .info-card:hover { border-color: var(--color-primary-light); }
        .info-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: 8px; }
        .info-card ul { list-style: none; padding-left: 0; }
        .info-card ul li { font-size: 0.84rem; color: var(--color-text-muted); margin-bottom: 6px; }
        .info-card ul li::before { content: '▸'; color: var(--color-primary); margin-right: 6px; font-size: 0.7rem; }
        /* 场景选择表 */
        .scene-table { width: 100%; max-width: 800px; margin: 16px auto; border-collapse: collapse; font-size: 0.85rem; }
        .scene-table th { background: #f1f5f9; padding: 10px 8px; text-align: left; font-weight: 600; }
        .scene-table td { padding: 10px 8px; border-bottom: 1px solid var(--color-border); }
        /* FAQ */
        .faq-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; max-width: 800px; margin: 20px auto; }
        .faq-card {
            background: var(--color-card); border: 1px solid var(--color-border); border-radius: var(--radius-sm);
            padding: 14px; cursor: pointer; transition: all var(--transition);
        }
        .faq-card:hover { border-color: var(--color-primary-light); }
        .faq-card details summary { font-weight: 600; font-size: 0.85rem; list-style: none; display: flex; justify-content: space-between; align-items: center; }
        .faq-card details summary::-webkit-details-marker { display: none; }
        .faq-card details summary::after { content: '▾'; color: var(--color-primary); }
        .faq-card details[open] summary::after { content: '▴'; }
        .faq-card details .answer { padding-top: 6px; font-size: 0.78rem; color: var(--color-text-muted); }
        /* 底部CTA */
        .cta-bottom {
            background: var(--color-footer-bg); color: #e2e8f0; padding: 40px 0; text-align: center;
        }
        .cta-bottom h2 { color: #fff; font-size: 1.6rem; margin-bottom: 8px; }
        .cta-bottom p { color: #cbd5e1; margin-bottom: 18px; font-size: 0.9rem; }
        .btn-cta-big {
            display: inline-block; background: var(--gradient-btn); color: #fff; font-weight: 700; padding: 14px 34px;
            border-radius: var(--radius-full); text-decoration: none; font-size: 1.05rem; transition: all 0.25s ease;
            box-shadow: 0 8px 20px -6px rgba(37,99,235,0.5);
        }
        .btn-cta-big:hover { background: var(--gradient-btn-hover); transform: translateY(-2px); box-shadow: 0 12px 26px -8px rgba(37,99,235,0.6); }
        .btn-outline-sm {
            display: inline-block; border: 1px solid var(--color-border); padding: 6px 14px; border-radius: var(--radius-full);
            font-size: 0.8rem; text-decoration: none; color: var(--color-text); transition: all var(--transition);
        }
        .btn-outline-sm:hover { border-color: var(--color-primary); color: var(--color-primary); }
        /* 页脚 */
        .footer {
            background: #0a0f1a; color: #cbd5e1; padding: 44px 0 24px; font-size: 0.82rem; border-top: 1px solid #1e293b;
        }
        .footer-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); gap: 30px; margin-bottom: 30px; }
        .footer-col h4 { color: #fff; margin-bottom: 12px; font-weight: 620; font-size: 0.85rem; }
        .footer-col a { display: block; color: #94a3b8; text-decoration: none; margin-bottom: 7px; transition: color var(--transition); font-size: 0.78rem; }
        .footer-col a:hover { color: #fff; }
        .copyright { text-align: center; padding-top: 22px; border-top: 1px solid #1e293b; color: #64748b; font-size: 0.72rem; }
        @media (max-width: 768px) {
            .grid-2col, .faq-grid { grid-template-columns: 1fr; }
            .subscribe-flow { flex-direction: column; }
            .flow-arrow { display: none; }
        }