:root {
            --primary-color: #e53e3e;
            --primary-hover: #c53030;
            --text-dark: #2a2a2d;
            --text-muted: #4b5563;
            --bg-light: #f8fafc;
            --bg-gradient: radial-gradient(circle at 50% 50%, #e0f2fe 0%, #ffffff 100%);
            --card-bg: #ffffff;
            --border-color: #e2e8f0;
            --accent-blue: #2563eb;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        body {
            font-family: 'Noto Sans SC', sans-serif;
            color: var(--text-dark);
            background-color: #ffffff;
            overflow-x: hidden;
            -webkit-font-smoothing: antialiased;
            line-height: 1.7;
        }
        .header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 20px 40px;
            margin: 0 auto;
            width: 100%;
            position: fixed;
            top: 0;
            left: 50%;
            transform: translateX(-50%);
            z-index: 10;
            background: #eff8ff;
            border-bottom: 1px solid rgba(62, 95, 255, 0.1);
        }
        .header-left, .header-right {
            display: flex;
            align-items: center;
            gap: 32px;
        }
        .logo {
            display: flex;
            align-items: center;
            gap: 8px;
            font-weight: 700;
            font-size: 22px;
            color: #0640b7;
            text-decoration: none;
        }
        .logo img {
            height: 32px;
            width: auto;
            display: block;
        }
        .nav-links {
            display: flex;
            gap: 24px;
            list-style: none;
        }
        .nav-item {
            display: flex;
            align-items: center;
            gap: 4px;
            font-size: 14px;
            font-weight: 500;
            cursor: pointer;
        }
        .nav-item a {
            color: var(--text-dark);
            text-decoration: none;
        }
        .nav-secondary {
            display: flex;
            align-items: center;
            gap: 20px;
            list-style: none;
            font-size: 14px;
        }
        .nav-secondary a {
            color: var(--text-dark);
            text-decoration: none;
        }
        .nav-secondary li {
            display: flex;
            align-items: center;
            gap: 4px;
        }
        .lang-selector {
            display: flex;
            align-items: center;
            cursor: pointer;
        }
        .btn-primary {
            background-color: var(--primary-color);
            color: #ffffff;
            padding: 10px 24px;
            border-radius: 9999px;
            font-weight: 700;
            text-decoration: none;
            font-size: 14px;
            transition: background-color 0.2s;
            border: none;
            cursor: pointer;
            display: inline-block;
            text-align: center;
        }
        .btn-primary:hover {
            background-color: var(--primary-hover);
        }
        .download-hero {
            background: var(--bg-gradient);
            padding: 180px 20px 80px 20px;
            text-align: center;
            border-bottom: 1px solid var(--border-color);
        }
        .hero-container {
            max-width: 720px;
            margin: 0 auto;
        }
        .hero-badge {
            color: var(--accent-blue);
            font-size: 14px;
            font-weight: 700;
            letter-spacing: 0.05em;
            margin-bottom: 16px;
            display: inline-block;
            text-transform: uppercase;
        }
        .hero-title {
            font-size: 46px;
            font-weight: 700;
            line-height: 1.25;
            color: #0f172a;
            margin-bottom: 24px;
        }
        .hero-desc {
            font-size: 18px;
            color: var(--text-muted);
            margin-bottom: 40px;
        }
        .action-box {
            max-width: 480px;
            margin: 0 auto 32px auto;
        }
        .btn-download-full {
            display: block;
            width: 100%;
            background-color: var(--primary-color);
            color: #ffffff;
            padding: 18px 32px;
            border-radius: 12px;
            font-weight: 700;
            font-size: 18px;
            text-decoration: none;
            transition: background-color 0.2s, transform 0.1s;
            border: none;
            cursor: pointer;
            box-shadow: 0 4px 14px rgba(229, 62, 62, 0.3);
            text-align: center;
        }
        .btn-download-full:hover {
            background-color: var(--primary-hover);
            transform: translateY(-1px);
        }
        .btn-download-full:active {
            transform: translateY(1px);
        }
        .hero-meta {
            font-size: 13px;
            color: var(--text-muted);
            display: flex;
            justify-content: center;
            gap: 24px;
        }
        .platforms-section {
            padding: 80px 40px;
            background-color: #ffffff;
        }
        .section-container {
            max-width: 1200px;
            margin: 0 auto;
        }
        .section-title {
            font-size: 32px;
            font-weight: 700;
            color: #0f172a;
            text-align: center;
            margin-bottom: 56px;
        }
        .platform-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 32px;
        }
        .platform-card {
            background: #ffffff;
            border: 1px solid var(--border-color);
            border-radius: 16px;
            padding: 32px;
            text-align: center;
            transition: transform 0.2s, box-shadow 0.2s;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }
        .platform-card:hover {
            transform: translateY(-4px);
            box-shadow: 0 12px 20px -3px rgba(0, 0, 0, 0.05);
            border-color: #cbd5e1;
        }
        .platform-icon {
            width: 48px;
            height: 48px;
            margin: 0 auto 20px auto;
            color: var(--accent-blue);
        }
        .platform-name {
            font-size: 20px;
            font-weight: 700;
            color: #1e293b;
            margin-bottom: 12px;
        }
        .platform-version {
            font-size: 13px;
            color: var(--text-muted);
            margin-bottom: 24px;
        }
        .btn-outline {
            display: block;
            border: 1px solid #cbd5e1;
            color: var(--text-dark);
            padding: 10px 20px;
            border-radius: 8px;
            text-decoration: none;
            font-size: 14px;
            font-weight: 500;
            transition: background-color 0.2s, border-color 0.2s;
            margin-top: 8px;
        }
        .btn-outline:hover {
            background-color: var(--bg-light);
            border-color: var(--text-dark);
        }

        /* 创意版块：快速下载通道 */
        .quick-download-section {
            padding: 60px 40px;
            background: #f0f4ff;
        }
        .quick-download-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 32px;
            max-width: 1100px;
            margin: 0 auto;
        }
        .quick-download-card {
            background: #fff;
            border-radius: 20px;
            padding: 36px 28px;
            text-align: center;
            border: 2px solid var(--border-color);
            transition: all 0.3s;
            position: relative;
        }
        .quick-download-card:hover {
            transform: translateY(-6px);
            box-shadow: 0 16px 36px rgba(0,0,0,0.08);
            border-color: var(--accent-blue);
        }
        .quick-download-card .card-icon {
            font-size: 44px;
            margin-bottom: 16px;
        }
        .quick-download-card h3 {
            font-size: 22px;
            font-weight: 700;
            color: #1e293b;
            margin-bottom: 8px;
        }
        .quick-download-card p {
            font-size: 14px;
            color: var(--text-muted);
            margin-bottom: 20px;
        }
        .btn-accent {
            background: var(--accent-blue);
            color: #fff;
            padding: 12px 28px;
            border-radius: 9999px;
            font-weight: 700;
            text-decoration: none;
            display: inline-block;
            transition: background 0.2s;
        }
        .btn-accent:hover {
            background: #1d4ed8;
        }
        .btn-accent-outline {
            border: 2px solid var(--accent-blue);
            color: var(--accent-blue);
            padding: 12px 28px;
            border-radius: 9999px;
            font-weight: 700;
            text-decoration: none;
            display: inline-block;
            transition: all 0.2s;
        }
        .btn-accent-outline:hover {
            background: var(--accent-blue);
            color: #fff;
        }

        /* 安装指南与升级亮点 */
        .install-guide-section {
            padding: 80px 40px;
            background-color: #f8fafc;
            border-top: 1px solid var(--border-color);
        }
        .guide-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 32px;
            margin-bottom: 64px;
        }
        .guide-card {
            background: #ffffff;
            border-radius: 16px;
            padding: 32px;
            text-align: center;
            border: 1px solid var(--border-color);
            transition: box-shadow 0.2s;
        }
        .guide-card:hover {
            box-shadow: 0 8px 16px rgba(0,0,0,0.04);
        }
        .guide-step {
            width: 48px;
            height: 48px;
            background-color: #e0f2fe;
            color: var(--accent-blue);
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 20px;
            font-weight: 700;
            margin: 0 auto 20px auto;
        }
        .guide-title {
            font-size: 20px;
            font-weight: 700;
            color: #0f172a;
            margin-bottom: 12px;
        }
        .guide-desc {
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.6;
        }
        .upgrade-highlight {
            background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
            border-radius: 20px;
            padding: 48px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            color: #ffffff;
            gap: 40px;
        }
        .upgrade-content {
            flex: 1;
        }
        .upgrade-badge {
            display: inline-block;
            background: rgba(255,255,255,0.1);
            padding: 6px 16px;
            border-radius: 20px;
            font-size: 13px;
            font-weight: 500;
            margin-bottom: 16px;
            color: #a5b4fc;
        }
        .upgrade-content h3 {
            font-size: 26px;
            font-weight: 700;
            margin-bottom: 16px;
        }
        .upgrade-content p {
            font-size: 15px;
            color: #cbd5e1;
            line-height: 1.6;
            margin-bottom: 24px;
            max-width: 600px;
        }
        .upgrade-content .btn-outline {
            display: inline-block;
            width: auto;
            padding: 10px 24px;
            border-color: #475569;
            color: #e2e8f0;
            background: transparent;
        }
        .upgrade-content .btn-outline:hover {
            background: rgba(255,255,255,0.05);
            border-color: #94a3b8;
        }
        .upgrade-image {
            flex-shrink: 0;
        }

        .site-footer {
            background-color: #0b0e17;
            color: #9ca3af;
            padding: 80px 40px 40px 40px;
            margin-top: 0;
        }
        .footer-container {
            max-width: 1200px;
            margin: 0 auto;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 40px;
            border-bottom: 1px solid #22293a;
            padding-bottom: 48px;
        }
        .footer-col h4 {
            color: #ffffff;
            font-size: 16px;
            font-weight: 700;
            margin-bottom: 24px;
        }
        .footer-links {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }
        .footer-links a {
            color: #9ca3af;
            text-decoration: none;
            font-size: 14px;
            transition: color 0.2s;
        }
        .footer-links a:hover {
            color: #ffffff;
        }

        /* 响应式调整 */
        @media (max-width: 1024px) {
            .platform-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .quick-download-grid {
                grid-template-columns: 1fr;
                max-width: 500px;
                margin: 0 auto;
            }
            .guide-grid {
                grid-template-columns: 1fr;
            }
            .upgrade-highlight {
                flex-direction: column;
                text-align: center;
            }
            .upgrade-content p {
                max-width: 100%;
            }
            .footer-grid {
                grid-template-columns: 1fr 1fr;
            }
        }
        @media (max-width: 768px) {
            .nav-links, .nav-secondary {
                display: none;
            }
            .download-hero {
                padding: 140px 20px 60px 20px;
            }
            .hero-title {
                font-size: 32px;
            }
            .hero-desc {
                font-size: 16px;
                margin-bottom: 32px;
            }
            .platform-grid {
                grid-template-columns: 1fr;
            }
            .footer-grid {
                grid-template-columns: 1fr;
            }
        }