: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——与首页完全一致 */
        .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; }
        }

        /* 页面顶部 */
        .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: 600px; margin: 0 auto; }

        /* 按钮通用 */
        .btn { display: inline-block; padding: 13px 26px; border-radius: 28px; font-weight: 600; text-decoration: none; font-size: 0.93rem; transition: var(--transition); letter-spacing: -0.1px; cursor: pointer; border: none; text-align: center; }
        .btn-primary { background: var(--accent); color: #fff; box-shadow: 0 4px 16px rgba(59,130,246,0.25); }
        .btn-primary:hover { background: #2563eb; box-shadow: 0 6px 24px rgba(59,130,246,0.35); transform: translateY(-2px); }
        .btn-outline { background: transparent; color: var(--accent); border: 1.5px solid var(--border); }
        .btn-outline:hover { border-color: var(--accent); background: var(--accent-soft); }

        /* 下载卡片样式（清爽版） */
        .platform-grid {
            display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; margin: 28px 0;
        }
        .platform-card {
            background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
            padding: 28px 24px; box-shadow: var(--shadow-sm); transition: var(--transition);
            display: flex; flex-direction: column;
        }
        .platform-card:hover { border-color: var(--accent-light); box-shadow: var(--shadow-lg); transform: translateY(-2px); }
        .platform-icon { font-size: 2.2rem; margin-bottom: 10px; }
        .platform-card h2 { font-size: 1.4rem; font-weight: 700; margin: 0 0 4px; letter-spacing: -0.3px; }
        .version-tag { display: inline-block; background: var(--accent-soft); color: var(--accent); font-size: 0.75rem; font-weight: 600; padding: 4px 12px; border-radius: 20px; margin-bottom: 12px; width: fit-content; }
        .platform-card p { color: var(--text2); font-size: 0.9rem; line-height: 1.5; margin: 0 0 12px; flex: 1; }
        .sys-req { font-size: 0.78rem; color: var(--text3); margin-bottom: 14px; }
        .btn-download {
            display: block; width: 100%; padding: 13px 18px; border-radius: 28px; font-weight: 600;
            text-decoration: none; font-size: 0.95rem; text-align: center; transition: var(--transition);
            background: var(--accent); color: #fff; margin-bottom: 10px;
            box-shadow: 0 4px 14px rgba(59,130,246,0.25);
        }
        .btn-download:hover { background: #2563eb; transform: translateY(-2px); box-shadow: 0 6px 20px rgba(59,130,246,0.35); }
        .btn-download.secondary { background: #10b981; }
        .btn-download.secondary:hover { background: #059669; }
        .file-details { font-size: 0.73rem; color: var(--text3); margin-bottom: 6px; }
        .checksum { font-size: 0.68rem; color: var(--text3); word-break: break-all; border-top: 1px solid var(--border); padding-top: 10px; margin-top: 8px; }

        /* 辅助决策区域 */
        .decision-helper {
            background: var(--accent-soft); border: 1px solid #bfdbfe; border-radius: var(--radius);
            padding: 18px 22px; display: flex; flex-wrap: wrap; gap: 16px; align-items: center;
            margin: 28px 0; box-shadow: var(--shadow-sm);
        }
        .dh-icon { font-size: 2rem; }
        .dh-text h3 { font-size: 1rem; font-weight: 700; margin-bottom: 2px; }
        .dh-text p { color: var(--text2); font-size: 0.82rem; margin: 0; }
        .dh-links { display: flex; gap: 10px; flex-wrap: wrap; margin-left: auto; }
        .dh-link { color: var(--accent); font-weight: 600; font-size: 0.85rem; text-decoration: none; padding: 6px 14px; border-radius: 20px; background: rgba(255,255,255,0.6); transition: var(--transition); }
        .dh-link:hover { background: #fff; }

        /* 安装流程 */
        .install-flow { margin: 36px 0; }
        .flow-title { font-size: 1.5rem; font-weight: 700; text-align: center; margin-bottom: 4px; }
        .flow-sub { text-align: center; color: var(--text2); font-size: 0.9rem; margin-bottom: 24px; }
        .timeline { display: flex; flex-wrap: wrap; gap: 16px; justify-content: center; }
        .timeline .step {
            flex: 1 1 180px; max-width: 220px; background: var(--surface); border: 1px solid var(--border);
            border-radius: var(--radius); padding: 22px 14px; text-align: center; box-shadow: var(--shadow-sm);
            transition: var(--transition);
        }
        .timeline .step:hover { border-color: var(--accent-light); transform: translateY(-2px); }
        .step-icon { font-size: 1.8rem; margin-bottom: 6px; }
        .timeline .step h3 { font-size: 0.95rem; font-weight: 700; margin: 0 0 4px; }
        .timeline .step p { color: var(--text2); font-size: 0.78rem; margin: 0; }

        /* 协议仪表盘 */
        .protocol-dashboard { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px 24px; margin: 28px 0; box-shadow: var(--shadow-sm); }
        .protocol-dashboard h2 { font-size: 1.3rem; font-weight: 700; margin: 0 0 4px; }
        .pd-sub { color: var(--text2); font-size: 0.85rem; margin-bottom: 16px; }
        .protocol-grid { display: flex; flex-wrap: wrap; gap: 10px; }
        .protocol-badge {
            display: flex; align-items: center; gap: 6px; background: var(--surface-alt);
            border: 1px solid var(--border); border-radius: 20px; padding: 6px 16px;
            font-size: 0.82rem; font-weight: 500;
        }
        .p-dot { width: 8px; height: 8px; border-radius: 50%; }
        .p-dot-green { background: var(--green); }
        .p-dot-amber { background: var(--orange); }
        .p-dot-purple { background: #8b5cf6; }

        /* 开发者资源 */
        .dev-resources {
            background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
            padding: 18px 22px; display: flex; flex-wrap: wrap; gap: 16px; align-items: center;
            justify-content: space-between; margin: 24px 0; box-shadow: var(--shadow-sm);
        }
        .dev-resources h3 { font-size: 1rem; font-weight: 700; margin: 0 0 2px; }
        .dev-links { display: flex; gap: 10px; flex-wrap: wrap; }
        .dev-link { color: var(--accent); font-weight: 600; font-size: 0.85rem; text-decoration: none; padding: 5px 12px; border-radius: 20px; background: var(--accent-soft); transition: var(--transition); }
        .dev-link:hover { background: #dbeafe; }

        /* 提示卡片 */
        .tips-area { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin: 28px 0; }
        .tip-card {
            background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
            padding: 18px 18px; box-shadow: var(--shadow-sm);
        }
        .tip-card h4 { font-size: 0.95rem; font-weight: 700; margin: 0 0 8px; }
        .tip-card ul { list-style: none; padding: 0; margin: 0; }
        .tip-card li { font-size: 0.8rem; color: var(--text2); margin-bottom: 4px; padding-left: 14px; position: relative; }
        .tip-card li::before { content: "•"; position: absolute; left: 0; color: var(--accent); }

        /* 下一步导航 */
        .next-steps { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin: 8px 0 32px; }
        .next-step-card {
            background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
            padding: 16px 20px; display: flex; align-items: center; gap: 10px; text-decoration: none;
            color: var(--text); font-weight: 600; font-size: 0.9rem; transition: var(--transition);
            box-shadow: var(--shadow-sm);
        }
        .next-step-card:hover { border-color: var(--accent-light); transform: translateY(-2px); box-shadow: var(--shadow-md); }
        .ns-icon { font-size: 1.3rem; }

        /* CTA返回 */
        .cta-return {
            background: linear-gradient(135deg, #eff6ff 0%, #dbeafe 100%);
            border: 1px solid #bfdbfe; border-radius: 20px; padding: 32px 24px;
            text-align: center; margin: 32px 0 20px;
        }
        .cta-return h2 { font-size: 1.5rem; font-weight: 700; margin-bottom: 6px; }
        .cta-return p { color: var(--text2); margin-bottom: 18px; }
        .btn-return { 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-return: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; }

        @media (max-width: 600px) {
            .platform-grid { grid-template-columns: 1fr; }
            .page-hero h1 { font-size: 1.5rem; }
            .decision-helper { flex-direction: column; align-items: flex-start; }
            .dh-links { margin-left: 0; }
        }