:root {
            --bg-deepest: #060b10;
            --bg-deep: #0a1018;
            --bg-surface: #0f1822;
            --bg-card: #141e2b;
            --bg-card-hover: #192638;
            --cyan-400: #22d3ee;
            --cyan-500: #06b6d4;
            --cyan-600: #0891b2;
            --cyan-700: #0e7490;
            --purple-400: #a78bfa;
            --purple-500: #8b5cf6;
            --purple-600: #7c3aed;
            --cyan-glow: rgba(6,182,212,0.35);
            --purple-glow: rgba(139,92,246,0.3);
            --text-primary: #e8edf3;
            --text-secondary: #bcc8d4;
            --text-muted: #7d8f9f;
            --text-dim: #5a6b7a;
            --border-subtle: rgba(56,189,248,0.08);
            --border-card: rgba(56,189,248,0.12);
            --border-glow: rgba(6,182,212,0.25);
            --radius-xs: 6px;
            --radius-sm: 10px;
            --radius-md: 16px;
            --radius-lg: 22px;
            --radius-xl: 30px;
            --radius-full: 9999px;
            --shadow-card: 0 2px 12px rgba(0,0,0,0.3);
            --shadow-card-hover: 0 12px 36px rgba(6,182,212,0.12), 0 2px 16px rgba(0,0,0,0.4);
            --ease-out: 0.2s cubic-bezier(0.4,0,0.2,1);
            --ease-spring: 0.3s cubic-bezier(0.34,1.56,0.64,1);
        }

        * { margin:0; padding:0; box-sizing:border-box; }
        html { scroll-behavior: smooth; font-size: 16px; }
        body {
            font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', 'Noto Sans SC', sans-serif;
            background: var(--bg-deepest);
            color: var(--text-primary);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
            min-height: 100vh;
            background-image: radial-gradient(ellipse at 20% 10%, rgba(6,182,212,0.04) 0%, transparent 60%),
                              radial-gradient(ellipse at 75% 50%, rgba(139,92,246,0.03) 0%, transparent 55%),
                              radial-gradient(ellipse at 40% 90%, rgba(6,182,212,0.03) 0%, transparent 50%);
            background-attachment: fixed;
        }
        .container { max-width: 1200px; margin:0 auto; padding:0 22px; }

        header {
            background: rgba(10,16,24,0.85); backdrop-filter: blur(18px);
            -webkit-backdrop-filter: blur(18px); position: sticky; top:0; z-index:100;
            border-bottom:1px solid var(--border-subtle);
            box-shadow:0 1px 0 rgba(6,182,212,0.04);
        }
        .nav-bar { display:flex; align-items:center; justify-content:space-between; flex-wrap:wrap; padding:12px 0; gap:12px; }
        .logo-area { display:flex; align-items:center; gap:8px; text-decoration:none; }
        .logo-icon {
            width:38px; height:38px; border-radius:var(--radius-sm);
            background:linear-gradient(135deg, var(--cyan-500), var(--purple-500));
            display:flex; align-items:center; justify-content:center;
            font-weight:900; font-size:1.1rem; color:#fff;
            box-shadow:0 0 18px var(--cyan-glow); transition:var(--ease-spring);
        }
        .logo-area:hover .logo-icon { box-shadow:0 0 28px var(--purple-glow); transform:scale(1.04); }
        .logo-text {
            font-weight:720; font-size:1.35rem; letter-spacing:-0.3px;
            background:linear-gradient(135deg, #e8edf3 0%, #38bdf8 50%, #a78bfa 100%);
            -webkit-background-clip:text; background-clip:text; color:transparent;
        }
        .nav-links { display:flex; gap:4px; align-items:center; flex-wrap:wrap; list-style:none; }
        .nav-links a {
            text-decoration:none; font-weight:500; color:var(--text-secondary);
            transition:var(--ease-out); font-size:0.88rem; padding:7px 13px; border-radius:22px; white-space:nowrap;
        }
        .nav-links a:hover, .nav-links a.active { color:var(--cyan-400); background:rgba(6,182,212,0.08); }
        .nav-links a.active { font-weight:620; background:rgba(6,182,212,0.13); box-shadow:inset 0 0 0 1px rgba(6,182,212,0.2); }
        .nav-download-btn {
            background:linear-gradient(135deg, var(--cyan-600), var(--cyan-500));
            color:#fff !important; padding:8px 18px; border-radius:28px; font-weight:600;
            transition:var(--ease-spring); box-shadow:0 0 16px var(--cyan-glow);
        }
        .nav-download-btn:hover {
            background:linear-gradient(135deg, var(--cyan-500), #22d3ee);
            box-shadow:0 0 28px rgba(6,182,212,0.5); transform:translateY(-2px);
        }

        .section-title {
            font-size:clamp(1.6rem,2.5vw,2rem); font-weight:720; margin-bottom:10px;
            color:#e0e8f2; letter-spacing:-0.2px; text-align:center;
        }
        .accent-dot {
            display:inline-block; width:8px; height:8px; border-radius:50%;
            background:var(--cyan-500); box-shadow:0 0 10px var(--cyan-glow);
            margin:0 6px; vertical-align:middle;
        }
        .accent-dot.purple { background:var(--purple-500); box-shadow:0 0 10px var(--purple-glow); }

        /* Tab 切换 */
        .tab-container { display:flex; justify-content:center; gap:14px; margin:32px 0 20px; flex-wrap:wrap; }
        .tab-btn {
            background:var(--bg-card); border:1px solid var(--border-card); color:var(--text-secondary);
            padding:12px 30px; border-radius:var(--radius-full); font-weight:600; font-size:0.95rem;
            cursor:pointer; transition:var(--ease-spring); display:inline-flex; align-items:center; gap:8px;
            user-select:none;
        }
        .tab-btn.active {
            background:linear-gradient(135deg, var(--cyan-600), var(--cyan-500));
            color:#fff; border-color:transparent; box-shadow:0 0 20px var(--cyan-glow);
            transform:scale(1.02);
        }
        .tab-pane { display:none; }
        .tab-pane.active { display:block; }

        /* 下载卡片 */
        .download-card {
            background:var(--bg-card); border-radius:var(--radius-xl); padding:32px 28px;
            border:1px solid var(--border-card); transition:var(--ease-out);
            margin-bottom:24px;
        }
        .download-card:hover { border-color:var(--border-glow); box-shadow:var(--shadow-card-hover); }
        .info-grid { display:grid; grid-template-columns: repeat(auto-fit, minmax(180px,1fr)); gap:18px; margin:20px 0; }
        .info-block {
            background:rgba(6,182,212,0.03); border-radius:var(--radius-md);
            padding:18px 16px; border:1px solid rgba(56,189,248,0.08);
        }
        .info-block h4 { font-size:0.7rem; text-transform:uppercase; letter-spacing:0.8px; color:var(--cyan-400); margin-bottom:8px; }
        .info-block .value { font-size:1.2rem; font-weight:700; color:#e0e8f2; }
        .info-block .sub { font-size:0.7rem; color:var(--text-dim); margin-top:4px; }
        .btn-download-large {
            display:inline-flex; align-items:center; gap:10px;
            background:linear-gradient(135deg, var(--cyan-500), #22d3ee);
            color:#060b10; padding:16px 38px; border-radius:48px; font-weight:700; font-size:1.05rem;
            text-decoration:none; transition:var(--ease-spring); box-shadow:0 0 30px var(--cyan-glow);
            border:none; cursor:pointer; margin-right:12px;
        }
        .btn-download-large:hover { transform:translateY(-3px); box-shadow:0 0 48px rgba(6,182,212,0.55); background:linear-gradient(135deg, #22d3ee, #67e8f9); }
        .btn-outline-light {
            display:inline-flex; align-items:center; gap:6px;
            background:transparent; border:1.6px solid rgba(6,182,212,0.5); color:var(--cyan-400);
            padding:14px 30px; border-radius:48px; font-weight:600; font-size:0.95rem;
            text-decoration:none; transition:var(--ease-spring);
        }
        .btn-outline-light:hover { background:rgba(6,182,212,0.07); border-color:var(--cyan-400); color:#38bdf8; }

        /* 安装指南折叠 */
        .install-details { margin-top:20px; }
        .install-details summary { font-weight:600; color:var(--cyan-400); cursor:pointer; padding:8px 0; transition:var(--ease-out); }
        .install-details summary:hover { color:#38bdf8; }
        .install-steps { background:rgba(6,182,212,0.04); border-radius:var(--radius-md); padding:20px; margin-top:8px; border:1px solid rgba(56,189,248,0.08); }
        .install-steps ol { padding-left:24px; color:var(--text-secondary); }
        .install-steps li { margin-bottom:10px; line-height:1.6; }

        /* 对比表格 */
        .compare-table {
            width:100%; border-collapse:collapse; margin-top:16px;
            background:var(--bg-card); border-radius:var(--radius-md); overflow:hidden; border:1px solid var(--border-card);
        }
        .compare-table th, .compare-table td {
            padding:14px 16px; text-align:left; border-bottom:1px solid rgba(255,255,255,0.03);
        }
        .compare-table th { background:rgba(6,182,212,0.06); color:var(--cyan-400); font-weight:600; font-size:0.8rem; }
        .compare-table td { color:var(--text-secondary); font-size:0.85rem; }
        .compare-table tr:hover td { background:rgba(6,182,212,0.03); }

        /* 安全模块 */
        .security-card {
            background:linear-gradient(135deg, rgba(6,182,212,0.05), rgba(139,92,246,0.03));
            border-radius:var(--radius-lg); padding:28px 24px;
            border:1px solid var(--border-card); margin:20px 0;
        }
        .security-card h3 { color:var(--cyan-400); margin-bottom:12px; }
        .security-card p { color:var(--text-secondary); font-size:0.9rem; margin-bottom:8px; }
        .hash-code {
            background:#0a121c; font-family:monospace; color:var(--cyan-400);
            padding:10px 16px; border-radius:var(--radius-sm); display:inline-block;
            word-break:break-all; font-size:0.8rem; margin:6px 0;
        }

        .bottom-cta-section { padding:28px 0 44px; }
        .bottom-cta {
            background:linear-gradient(155deg, #0c1a26 0%, #111f2e 35%, #0f1a28 70%, #131e30 100%);
            border-radius:var(--radius-xl); padding:42px 26px; text-align:center; color:#fff;
            box-shadow:0 0 50px rgba(6,182,212,0.1); border:1px solid rgba(6,182,212,0.15);
            position:relative; overflow:hidden;
        }
        .bottom-cta::before {
            content:''; position:absolute; top:-60%; right:-25%;
            width:400px; height:400px; background:radial-gradient(circle, rgba(6,182,212,0.07) 0%, transparent 70%);
            border-radius:50%; pointer-events:none;
        }
        .bottom-cta h2 { font-size:clamp(1.5rem,2.5vw,1.8rem); font-weight:720; margin-bottom:8px; position:relative; z-index:1; }
        .bottom-cta p { font-size:0.95rem; opacity:0.85; max-width:540px; margin:0 auto 22px; position:relative; z-index:1; color:#cbd5e1; }
        .btn-cta-large {
            display:inline-flex; align-items:center; gap:10px;
            background:linear-gradient(135deg, var(--cyan-500), #22d3ee);
            color:#060b10; padding:14px 34px; border-radius:40px; font-weight:700; font-size:1.02rem;
            text-decoration:none; transition:var(--ease-spring); box-shadow:0 0 30px var(--cyan-glow);
        }
        .btn-cta-large:hover { transform:translateY(-3px); box-shadow:0 0 48px rgba(6,182,212,0.55); background:linear-gradient(135deg, #22d3ee, #67e8f9); }

        .footer {
            background:#060d14; color:#7d8f9f; padding:40px 0 18px;
            border-top:1px solid var(--border-subtle);
            border-top-left-radius:24px; border-top-right-radius:24px;
        }
        .footer-content { display:flex; flex-wrap:wrap; justify-content:space-between; gap:24px; }
        .footer-content h4 { color:#cbd5e1; margin-bottom:8px; font-size:0.95rem; font-weight:620; }
        .footer-content p { font-size:0.8rem; line-height:1.55; }
        .footer-content a { color:#7d8f9f; text-decoration:none; }
        .footer-content a:hover { color:var(--cyan-400); text-decoration:underline; }
        .footer-copyright {
            text-align:center; padding-top:24px; font-size:0.75rem;
            border-top:1px solid rgba(255,255,255,0.04); margin-top:16px; opacity:0.7; color:#5a6b7a;
        }
        .related-links { display:flex; flex-wrap:wrap; gap:12px; justify-content:center; margin-top:22px; }
        .related-link-card {
            background:var(--bg-card); border:1px solid var(--border-card); border-radius:28px;
            padding:10px 20px; color:var(--text-secondary); text-decoration:none;
            font-weight:500; font-size:0.88rem; transition:var(--ease-out);
        }
        .related-link-card:hover { border-color:var(--cyan-500); color:var(--cyan-400); background:rgba(6,182,212,0.06); }

        @media (max-width:768px) {
            .nav-bar { flex-direction:column; align-items:flex-start; }
        }