*,
        *::before,
        *::after {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        :root {
            --bg: #f0f4fb;
            --surface: #ffffff;
            --primary: #1a2b4a;
            --accent: #4f7cf7;
            --accent2: #6c8cfa;
            --accent-light: #eef3fe;
            --text: #1a2b4a;
            --text-muted: #5a6f8c;
            --text-light: #8a9fb5;
            --border: #dce6f0;
            --shadow: 0 12px 40px rgba(79, 124, 247, 0.10);
            --radius: 20px;
            --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            --gradient-accent: linear-gradient(135deg, #4f7cf7, #6c8cfa);
        }
        html {
            scroll-behavior: smooth;
            font-size: 16px;
        }
        body {
            font-family: var(--font);
            background: var(--bg);
            color: var(--text);
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }
        a {
            color: var(--accent);
            text-decoration: none;
            transition: color 0.2s;
        }
        a:hover {
            color: var(--primary);
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 24px;
        }

        /* Header (与首页一致) */
        .header {
            background: rgba(255, 255, 255, 0.88);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border-bottom: 1px solid var(--border);
            position: sticky;
            top: 0;
            z-index: 100;
            padding: 12px 0;
        }
        .header-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 16px;
        }
        .logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-weight: 700;
            font-size: 1.5rem;
            color: var(--primary);
        }
        .logo-icon {
            width: 40px;
            height: 40px;
            background: var(--gradient-accent);
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.3rem;
            font-weight: 800;
            color: #fff;
        }
        .logo-version {
            font-size: 0.65rem;
            background: var(--accent);
            color: #fff;
            padding: 2px 12px;
            border-radius: 40px;
            font-weight: 600;
            letter-spacing: 0.3px;
            margin-left: 4px;
        }
        .nav {
            display: flex;
            align-items: center;
            gap: 32px;
            flex-wrap: wrap;
        }
        .nav a {
            color: var(--text-muted);
            font-weight: 500;
            font-size: 0.95rem;
            padding: 4px 0;
            border-bottom: 2px solid transparent;
            transition: all 0.2s;
        }
        .nav a:hover,
        .nav a.active {
            color: var(--primary);
            border-bottom-color: var(--accent);
        }
        .nav a.active {
            font-weight: 600;
        }
        .nav-badge {
            background: var(--accent);
            color: #fff;
            font-size: 0.7rem;
            font-weight: 600;
            padding: 4px 14px;
            border-radius: 40px;
            letter-spacing: 0.4px;
            text-transform: uppercase;
        }
        .mobile-toggle {
            display: none;
            flex-direction: column;
            gap: 5px;
            background: none;
            border: none;
            cursor: pointer;
            padding: 6px;
        }
        .mobile-toggle span {
            width: 26px;
            height: 2.5px;
            background: var(--primary);
            border-radius: 4px;
            transition: 0.3s;
        }

        /* Hero */
        .page-hero {
            padding: 48px 0 24px;
            background: var(--bg);
            position: relative;
            overflow: hidden;
        }
        .page-hero::before {
            content: "";
            position: absolute;
            top: -80px;
            right: -60px;
            width: 320px;
            height: 320px;
            background: radial-gradient(circle, rgba(79,124,247,0.12), transparent 70%);
            border-radius: 50%;
            pointer-events: none;
        }
        .page-hero .container {
            position: relative;
            z-index: 1;
        }
        .page-hero h1 {
            font-size: 3rem;
            font-weight: 800;
            letter-spacing: -0.02em;
            color: var(--primary);
            margin-bottom: 8px;
            line-height: 1.15;
        }
        .page-hero h1 .highlight {
            background: var(--gradient-accent);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .page-hero .subhead {
            color: var(--text-muted);
            font-size: 1.2rem;
            max-width: 720px;
            margin-bottom: 20px;
        }
        .hero-stats-row {
            display: flex;
            flex-wrap: wrap;
            gap: 16px;
            margin-bottom: 18px;
        }
        .hero-stats-row span {
            background: var(--surface);
            border: 1px solid var(--border);
            padding: 6px 20px;
            border-radius: 40px;
            font-size: 0.85rem;
            color: var(--text-muted);
            box-shadow: 0 2px 8px rgba(0,0,0,0.02);
        }
        .hero-stats-row strong {
            color: var(--accent);
            font-weight: 700;
        }

        /* Official Badge */
        .official-badge {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: #e8f5e9;
            color: #2e7d32;
            font-weight: 600;
            font-size: 0.8rem;
            padding: 6px 18px;
            border-radius: 40px;
            margin-bottom: 14px;
            border: 1px solid #c8e6c9;
        }

        /* Download Cards */
        .download-section {
            padding: 30px 0 60px;
            background: var(--bg);
        }
        .download-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 28px;
        }
        .download-card {
            background: var(--surface);
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 28px 26px;
            box-shadow: var(--shadow);
            transition: border-color 0.3s, box-shadow 0.3s, transform 0.3s;
            display: flex;
            flex-direction: column;
        }
        .download-card:hover {
            border-color: var(--accent);
            box-shadow: 0 16px 48px rgba(79, 124, 247, 0.12);
            transform: translateY(-3px);
        }
        .download-card .card-top {
            display: flex;
            align-items: center;
            gap: 14px;
            margin-bottom: 10px;
        }
        .platform-icon {
            font-size: 2.6rem;
            line-height: 1;
        }
        .platform-info .platform-name {
            font-size: 1.4rem;
            font-weight: 700;
            color: var(--primary);
        }
        .platform-info .platform-desc {
            color: var(--text-muted);
            font-size: 0.9rem;
        }
        .version-tag {
            display: inline-block;
            background: var(--accent-light);
            color: var(--accent);
            font-weight: 600;
            font-size: 0.75rem;
            padding: 2px 14px;
            border-radius: 40px;
            margin-bottom: 14px;
            align-self: flex-start;
        }
        .download-actions {
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
            margin: 10px 0 6px;
        }
        .btn-download {
            background: var(--gradient-accent);
            color: #fff;
            padding: 12px 30px;
            border-radius: 60px;
            font-weight: 700;
            font-size: 0.95rem;
            border: none;
            cursor: pointer;
            transition: all 0.25s;
            display: inline-flex;
            align-items: center;
            gap: 8px;
            box-shadow: 0 6px 20px rgba(79, 124, 247, 0.2);
        }
        .btn-download:hover {
            transform: translateY(-2px);
            box-shadow: 0 10px 32px rgba(79, 124, 247, 0.3);
            color: #fff;
        }
        .btn-outline {
            background: transparent;
            border: 1px solid var(--border);
            color: var(--text-muted);
            padding: 12px 24px;
            border-radius: 60px;
            font-weight: 600;
            font-size: 0.9rem;
            cursor: pointer;
            transition: all 0.25s;
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }
        .btn-outline:hover {
            background: var(--accent-light);
            border-color: var(--accent);
            color: var(--primary);
        }
        .checksum {
            font-size: 0.75rem;
            color: var(--text-light);
            margin-top: 8px;
            font-family: monospace;
            word-break: break-all;
        }
        .version-log {
            margin-top: 16px;
            border-top: 1px solid var(--border);
            padding-top: 14px;
            flex: 1;
        }
        .version-log h4 {
            font-size: 0.8rem;
            font-weight: 600;
            color: var(--text-muted);
            margin-bottom: 6px;
            text-transform: uppercase;
            letter-spacing: 0.5px;
        }
        .version-log ul {
            list-style: none;
            padding: 0;
        }
        .version-log ul li {
            display: flex;
            flex-wrap: wrap;
            gap: 8px 20px;
            font-size: 0.8rem;
            color: var(--text-muted);
            padding: 4px 0;
            border-bottom: 1px solid rgba(0,0,0,0.03);
        }
        .version-log ul li .v {
            color: var(--accent);
            font-weight: 600;
            min-width: 70px;
        }
        .version-log ul li .d {
            color: var(--text-light);
            min-width: 90px;
        }
        .version-log ul li .c {
            color: var(--text-muted);
        }

        /* Section Common */
        .section-label {
            display: inline-block;
            font-size: 0.75rem;
            text-transform: uppercase;
            letter-spacing: 1.5px;
            color: var(--accent);
            font-weight: 700;
            background: var(--accent-light);
            padding: 4px 18px;
            border-radius: 40px;
            margin-bottom: 12px;
        }
        .section-title {
            font-size: 2.4rem;
            font-weight: 700;
            letter-spacing: -0.02em;
            margin-bottom: 12px;
            color: var(--primary);
        }
        .section-title .highlight {
            background: var(--gradient-accent);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .section-desc {
            color: var(--text-muted);
            font-size: 1.1rem;
            max-width: 680px;
            margin-bottom: 36px;
        }

        /* Security Shield */
        .security-shield {
            padding: 60px 0;
            background: var(--surface);
            border-top: 1px solid var(--border);
        }
        .shield-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
            gap: 28px;
        }
        .shield-card {
            background: var(--bg);
            border: 1px solid var(--border);
            border-radius: 16px;
            padding: 28px 22px;
            text-align: center;
            transition: all 0.3s;
        }
        .shield-card:hover {
            border-color: var(--accent);
            box-shadow: var(--shadow);
        }
        .shield-card .shield-icon {
            font-size: 2.4rem;
            margin-bottom: 10px;
        }
        .shield-card h4 {
            font-size: 1.1rem;
            font-weight: 600;
            color: var(--primary);
            margin-bottom: 6px;
        }
        .shield-card p {
            font-size: 0.9rem;
            color: var(--text-muted);
        }

        /* AI Protocol Highlight */
        .ai-protocol {
            padding: 60px 0;
            background: var(--bg);
            border-top: 1px solid var(--border);
        }
        .ai-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 40px;
            align-items: center;
        }
        .ai-visual {
            background: var(--surface);
            border-radius: var(--radius);
            border: 1px solid var(--border);
            padding: 30px;
            box-shadow: var(--shadow);
            display: flex;
            flex-wrap: wrap;
            gap: 16px;
            justify-content: center;
        }
        .ai-tag {
            background: var(--accent-light);
            color: var(--accent);
            font-weight: 600;
            font-size: 0.85rem;
            padding: 8px 20px;
            border-radius: 40px;
            border: 1px solid #c5d4f7;
        }
        .ai-text h3 {
            font-size: 1.8rem;
            font-weight: 700;
            color: var(--primary);
            margin-bottom: 10px;
        }
        .ai-text p {
            color: var(--text-muted);
            font-size: 1rem;
            margin-bottom: 16px;
        }
        .ai-text ul {
            list-style: none;
            padding: 0;
        }
        .ai-text ul li {
            margin-bottom: 8px;
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 0.95rem;
            color: var(--text-muted);
        }

        /* Install Steps */
        .install-steps {
            padding: 60px 0;
            background: var(--surface);
            border-top: 1px solid var(--border);
        }
        .steps-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 24px;
            margin-top: 20px;
        }
        .step-card {
            background: var(--bg);
            border: 1px solid var(--border);
            border-radius: 16px;
            padding: 28px 22px;
            text-align: center;
            position: relative;
            transition: all 0.3s;
        }
        .step-card:hover {
            border-color: var(--accent);
            box-shadow: var(--shadow);
        }
        .step-number {
            width: 40px;
            height: 40px;
            background: var(--gradient-accent);
            color: #fff;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 1.2rem;
            margin: 0 auto 12px;
        }
        .step-card h4 {
            font-weight: 600;
            font-size: 1.05rem;
            color: var(--primary);
            margin-bottom: 6px;
        }
        .step-card p {
            font-size: 0.85rem;
            color: var(--text-muted);
        }

        /* System Requirements Table */
        .system-req {
            padding: 60px 0;
            background: var(--bg);
            border-top: 1px solid var(--border);
        }
        .req-table {
            background: var(--surface);
            border: 1px solid var(--border);
            border-radius: 16px;
            overflow: hidden;
            box-shadow: var(--shadow);
        }
        .req-table table {
            width: 100%;
            border-collapse: collapse;
            font-size: 0.9rem;
        }
        .req-table th,
        .req-table td {
            padding: 14px 20px;
            text-align: left;
            border-bottom: 1px solid var(--border);
        }
        .req-table th {
            background: var(--accent-light);
            color: var(--primary);
            font-weight: 600;
        }
        .req-table tr:last-child td {
            border-bottom: none;
        }
        .req-table td:first-child {
            font-weight: 600;
            color: var(--primary);
        }

        /* Download FAQ */
        .download-faq {
            padding: 60px 0;
            background: var(--surface);
            border-top: 1px solid var(--border);
        }
        .faq-grid {
            display: grid;
            grid-template-columns: 1fr;
            gap: 16px;
            max-width: 800px;
            margin-top: 20px;
        }
        .faq-item {
            background: var(--bg);
            border: 1px solid var(--border);
            border-radius: 12px;
            padding: 18px 22px;
            transition: 0.3s;
        }
        .faq-item:hover {
            border-color: var(--accent);
            box-shadow: var(--shadow);
        }
        .faq-item h4 {
            font-weight: 600;
            font-size: 1rem;
            color: var(--primary);
            margin-bottom: 6px;
        }
        .faq-item p {
            font-size: 0.9rem;
            color: var(--text-muted);
        }

        /* CTA */
        .cta-section {
            padding: 50px 0;
            background: var(--gradient-accent);
            color: #fff;
        }
        .cta-inner {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            justify-content: space-between;
            gap: 24px;
        }
        .cta-inner h2 {
            font-size: 2rem;
            font-weight: 700;
            letter-spacing: -0.02em;
        }
        .cta-inner p {
            font-size: 1rem;
            opacity: 0.9;
            max-width: 400px;
        }
        .cta-inner .btn-white {
            background: #fff;
            color: var(--primary);
            padding: 14px 38px;
            border-radius: 60px;
            font-weight: 700;
            font-size: 1rem;
            border: none;
            cursor: pointer;
            transition: all 0.25s;
            display: inline-flex;
            align-items: center;
            gap: 10px;
            box-shadow: 0 8px 28px rgba(0,0,0,0.15);
        }
        .cta-inner .btn-white:hover {
            transform: translateY(-3px);
            box-shadow: 0 14px 40px rgba(0,0,0,0.25);
        }

        /* Footer (与首页一致) */
        .footer {
            background: var(--primary);
            color: rgba(255,255,255,0.7);
            padding: 40px 0 28px;
            border-top: 1px solid rgba(255,255,255,0.06);
        }
        .footer a {
            color: rgba(255,255,255,0.6);
        }
        .footer a:hover {
            color: #fff;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 40px;
            margin-bottom: 28px;
        }
        .footer-brand .logo {
            color: #fff;
            margin-bottom: 8px;
        }
        .footer-brand p {
            font-size: 0.9rem;
            max-width: 360px;
            color: rgba(255,255,255,0.6);
        }
        .footer-brand .entity {
            font-size: 0.8rem;
            color: rgba(255,255,255,0.35);
            margin-top: 12px;
            display: flex;
            flex-wrap: wrap;
            gap: 20px;
        }
        .footer-col h5 {
            color: #fff;
            font-weight: 600;
            font-size: 0.9rem;
            margin-bottom: 12px;
        }
        .footer-col ul {
            list-style: none;
            padding: 0;
        }
        .footer-col ul li {
            margin-bottom: 8px;
        }
        .footer-col ul li a {
            font-size: 0.85rem;
            transition: 0.2s;
        }
        .footer-bottom {
            border-top: 1px solid rgba(255,255,255,0.06);
            padding-top: 20px;
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            align-items: center;
            font-size: 0.8rem;
            color: rgba(255,255,255,0.35);
        }

        @media (max-width: 1024px) {
            .download-grid {
                grid-template-columns: 1fr 1fr;
            }
            .ai-grid {
                grid-template-columns: 1fr;
            }
            .footer-grid {
                grid-template-columns: 1fr 1fr;
            }
        }
        @media (max-width: 768px) {
            .mobile-toggle {
                display: flex;
            }
            .nav {
                display: none;
                width: 100%;
                flex-direction: column;
                align-items: flex-start;
                gap: 12px;
                padding: 16px 0 8px;
                border-top: 1px solid var(--border);
                margin-top: 8px;
            }
            .nav.open {
                display: flex;
            }
            .nav a {
                font-size: 1rem;
            }
            .page-hero h1 {
                font-size: 2.2rem;
            }
            .section-title {
                font-size: 2rem;
            }
            .download-grid {
                grid-template-columns: 1fr;
            }
            .shield-grid,
            .steps-grid {
                grid-template-columns: 1fr 1fr;
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 24px;
            }
            .footer-bottom {
                flex-direction: column;
                align-items: flex-start;
                gap: 12px;
            }
        }
        @media (max-width: 480px) {
            .container {
                padding: 0 16px;
            }
            .page-hero h1 {
                font-size: 1.8rem;
            }
            .shield-grid,
            .steps-grid {
                grid-template-columns: 1fr;
            }
            .download-actions {
                flex-direction: column;
                align-items: stretch;
            }
            .btn-download,
            .btn-outline,
            .cta-inner .btn-white {
                width: 100%;
                justify-content: center;
            }
            .logo {
                font-size: 1.2rem;
            }
            .logo-version {
                font-size: 0.55rem;
                padding: 1px 10px;
            }
        }