:root {
            --bg: #f5f6f8;
            --surface: #ffffff;
            --surface-alt: #f9fafb;
            --border: #e5e7eb;
            --border-hover: #cbd5e1;
            --text: #1e293b;
            --text2: #64748b;
            --text3: #94a3b8;
            --accent: #3b82f6;
            --accent-light: #60a5fa;
            --accent-soft: #eff6ff;
            --green: #10b981;
            --green-soft: #ecfdf5;
            --orange: #f59e0b;
            --radius: 14px;
            --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
            --shadow-md: 0 4px 16px rgba(0,0,0,0.06),0 1px 3px rgba(0,0,0,0.04);
            --shadow-lg: 0 12px 32px rgba(0,0,0,0.07),0 2px 6px rgba(0,0,0,0.03);
            --transition: 0.22s cubic-bezier(0.4,0,0.2,1);
        }
        * { box-sizing: border-box; margin: 0; padding: 0; }
        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
            background: var(--bg); color: var(--text); line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }
        .container { max-width: 1080px; margin: 0 auto; padding: 0 20px; }

        /* 导航栏——与首页统一 */
        .navbar {
            background: rgba(255,255,255,0.82); backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px); border-bottom: 1px solid var(--border);
            position: sticky; top: 0; z-index: 100;
        }
        .nav-inner {
            display: flex; align-items: center; justify-content: space-between;
            flex-wrap: wrap; gap: 8px; padding: 10px 0;
        }
        .logo { font-weight: 700; font-size: 1.25rem; color: var(--text); letter-spacing: -0.4px; white-space: nowrap; }
        .logo .dot { color: var(--accent); font-weight: 800; }
        .nav-links { display: flex; align-items: center; gap: 2px; flex-wrap: wrap; }
        .nav-links a {
            color: var(--text2); text-decoration: none; padding: 7px 13px;
            border-radius: 20px; font-size: 0.88rem; font-weight: 500;
            transition: var(--transition); white-space: nowrap; letter-spacing: -0.1px;
        }
        .nav-links a:hover { color: var(--accent); background: var(--accent-soft); }
        .nav-links a.active { color: var(--accent); background: var(--accent-soft); font-weight: 600; }
        .nav-links a.nav-cta {
            background: var(--accent); color: #fff; border-radius: 20px;
            padding: 8px 18px; font-weight: 600; margin-left: 4px;
            box-shadow: 0 2px 12px rgba(59,130,246,0.25); transition: var(--transition);
        }
        .nav-links a.nav-cta:hover { background: #2563eb; box-shadow: 0 4px 20px rgba(59,130,246,0.35); transform: translateY(-1px); color: #fff; }
        .nav-flow-sep { color: var(--text3); font-size: 0.65rem; margin: 0 1px; user-select: none; pointer-events: none; }
        @media (max-width: 768px) {
            .nav-flow-sep { display: none; }
            .nav-links a { padding: 6px 10px; font-size: 0.78rem; border-radius: 16px; }
            .nav-links a.nav-cta { padding: 7px 14px; margin-left: 0; }
            .logo { font-size: 1.1rem; }
        }

        /* 页面头部 */
        .page-hero {
            background: var(--surface); border: 1px solid var(--border);
            border-radius: 20px; padding: 36px 28px; margin: 28px 0 24px;
            box-shadow: var(--shadow-md); text-align: center;
        }
        .eyebrow { color: var(--accent); font-weight: 600; font-size: 0.85rem; letter-spacing: 0.4px; margin-bottom: 8px; }
        .page-hero h1 { font-size: 2rem; font-weight: 700; letter-spacing: -0.5px; margin: 0 0 8px; }
        .page-hero p { color: var(--text2); font-size: 1rem; max-width: 650px; margin: 0 auto; }

        .section { padding: 18px 0; }
        .section-title { font-size: 1.5rem; font-weight: 700; text-align: center; margin: 0 0 6px; letter-spacing: -0.3px; }
        .section-sub { text-align: center; color: var(--text2); font-size: 0.9rem; margin: 0 0 24px; }

        /* 时间轴卡片 */
        .timeline-card {
            background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
            padding: 22px 24px; margin-bottom: 20px; box-shadow: var(--shadow-sm);
            position: relative; transition: var(--transition);
        }
        .timeline-card:hover { border-color: var(--accent-light); }
        .version-badge {
            display: inline-block; background: var(--accent); color: #fff; font-weight: 700;
            padding: 6px 18px; border-radius: 20px; font-size: 0.9rem; margin-bottom: 14px;
        }
        .version-date { color: var(--text3); font-size: 0.8rem; margin-left: 10px; }
        .feature-block { display: flex; flex-wrap: wrap; gap: 20px; margin-top: 12px; }
        .feature-col { flex: 1 1 200px; }
        .feature-col h4 { font-size: 0.95rem; font-weight: 700; margin-bottom: 8px; display: flex; align-items: center; gap: 6px; }
        .feature-col ul { list-style: none; padding: 0; }
        .feature-col li { font-size: 0.85rem; color: var(--text2); padding: 4px 0; padding-left: 18px; position: relative; }
        .feature-col li::before { content: "▹"; position: absolute; left: 0; color: var(--accent); font-weight: 700; }
        .new-tag { background: var(--green-soft); color: var(--green); padding: 2px 8px; border-radius: 10px; font-size: 0.7rem; font-weight: 600; }
        .fix-tag { background: #fef3c7; color: #b45309; padding: 2px 8px; border-radius: 10px; font-size: 0.7rem; font-weight: 600; }

        /* 折叠历史版本 */
        .history-toggle {
            background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
            padding: 12px 22px; margin: 20px 0; display: flex; align-items: center; justify-content: space-between;
            cursor: pointer; font-weight: 600; box-shadow: var(--shadow-sm); transition: var(--transition);
        }
        .history-toggle:hover { border-color: var(--accent-light); }
        .history-panel { display: none; }
        .history-panel.open { display: block; }
        .history-item {
            background: var(--surface-alt); border: 1px solid var(--border); border-radius: 12px;
            padding: 14px 18px; margin-bottom: 10px;
        }
        .history-item h3 { font-size: 0.95rem; font-weight: 700; }

        /* 影响分析区 */
        .impact-card {
            background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
            border: 1px solid #bae6fd; border-radius: var(--radius); padding: 22px 24px;
            margin: 28px 0; display: grid; grid-template-columns: 1fr 1fr; gap: 18px;
            box-shadow: var(--shadow-sm);
        }
        .impact-card h3 { font-weight: 700; font-size: 1.2rem; margin-bottom: 10px; }
        .impact-card p { color: var(--text2); font-size: 0.88rem; }
        .impact-links { margin-top: 12px; display: flex; gap: 8px; flex-wrap: wrap; }
        .impact-link {
            background: #fff; border: 1px solid var(--border); border-radius: 16px;
            padding: 5px 14px; font-size: 0.78rem; font-weight: 600; color: var(--accent);
            text-decoration: none; transition: var(--transition);
        }
        .impact-link:hover { background: var(--accent-soft); border-color: var(--accent); }
        @media (max-width: 600px) { .impact-card { grid-template-columns: 1fr; } }

        /* 趋势分析 */
        .trend-box {
            background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
            padding: 20px 22px; margin: 24px 0; box-shadow: var(--shadow-sm);
            text-align: center;
        }
        .trend-tags { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-top: 14px; }
        .trend-tag {
            background: var(--accent-soft); border: 1px solid #bfdbfe; border-radius: 20px;
            padding: 8px 18px; font-weight: 600; font-size: 0.9rem; color: var(--accent);
        }

        /* 订阅提醒 */
        .reminder-card {
            background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
            padding: 22px 24px; margin: 28px 0; box-shadow: var(--shadow-sm);
            text-align: center;
        }
        .reminder-card h2 { font-weight: 700; margin-bottom: 8px; }
        .reminder-card ul { list-style: none; padding: 0; margin: 16px 0; display: flex; flex-wrap: wrap; gap: 14px; justify-content: center; }
        .reminder-card li { display: flex; align-items: center; gap: 6px; font-size: 0.88rem; color: var(--text2); }

        /* 底部矩阵 */
        .bottom-matrix {
            display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin: 20px 0 28px;
        }
        .matrix-item {
            background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
            padding: 16px 20px; text-decoration: none; color: var(--text); font-weight: 600;
            font-size: 0.88rem; display: flex; align-items: center; gap: 8px;
            box-shadow: var(--shadow-sm); transition: var(--transition);
        }
        .matrix-item:hover { border-color: var(--accent-light); transform: translateY(-2px); box-shadow: var(--shadow-md); }
        .matrix-icon { font-size: 1.3rem; }

        /* CTA */
        .cta-download {
            background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
            border: 1px solid #bfdbfe; border-radius: 20px; padding: 32px 24px;
            text-align: center; margin: 24px 0 20px;
        }
        .cta-download h2 { font-size: 1.5rem; font-weight: 700; margin-bottom: 6px; }
        .cta-download p { color: var(--text2); margin-bottom: 18px; }
        .btn-download-cta {
            display: inline-block; padding: 12px 28px; border-radius: 28px; font-weight: 700;
            text-decoration: none; background: var(--accent); color: #fff;
            box-shadow: 0 4px 16px rgba(59,130,246,0.3); transition: var(--transition);
        }
        .btn-download-cta:hover { background: #2563eb; transform: translateY(-2px); box-shadow: 0 6px 22px rgba(59,130,246,0.4); }

        /* Footer */
        .footer {
            border-top: 1px solid var(--border); padding: 22px 16px; text-align: center; background: var(--surface); margin-top: 20px;
        }
        .footer-links { display: flex; flex-wrap: wrap; gap: 14px; justify-content: center; margin-bottom: 10px; }
        .footer-links a { color: var(--text2); text-decoration: none; font-size: 0.8rem; transition: var(--transition); }
        .footer-links a:hover { color: var(--accent); }
        .copyright { color: var(--text3); font-size: 0.7rem; }