* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        
        :root {
            --primary-color: #2563eb;
            --primary-dark: #1d4ed8;
            --secondary-color: #10b981;
            --accent-color: #f59e0b;
            --text-dark: #1f2937;
            --text-light: #6b7280;
            --bg-light: #f3f4f6;
            --bg-white: #ffffff;
            --border-color: #e5e7eb;
        }
        
        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            line-height: 1.6;
            color: var(--text-dark);
            background-color: var(--bg-light);
            overflow-x: hidden;
        }
        
        /* 容器 */
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        
        /* 头部导航 */
        header {
            background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
            color: white;
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
        }
        
        .header-content {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 15px 0;
        }
        
        .logo {
            font-size: 24px;
            font-weight: bold;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        
        .logo-icon {
            width: 40px;
            height: 40px;
            background: white;
            border-radius: 8px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--primary-color);
            font-weight: bold;
            font-size: 20px;
        }
        
        /* 桌面导航 */
        .desktop-nav {
            display: flex;
            gap: 30px;
            align-items: center;
        }
        
        .desktop-nav a {
            color: white;
            text-decoration: none;
            font-weight: 500;
            transition: opacity 0.3s;
        }
        
        .desktop-nav a:hover {
            opacity: 0.8;
        }
        
        /* 语言切换器 */
        .lang-switcher {
            position: relative;
        }
        
        .lang-btn {
            background: rgba(255,255,255,0.2);
            border: 1px solid rgba(255,255,255,0.3);
            color: white;
            padding: 8px 15px;
            border-radius: 6px;
            cursor: pointer;
            display: flex;
            align-items: center;
            gap: 5px;
            font-size: 14px;
            transition: all 0.3s;
        }
        
        .lang-btn:hover {
            background: rgba(255,255,255,0.3);
        }
        
        .lang-dropdown {
            position: absolute;
            top: 100%;
            right: 0;
            margin-top: 5px;
            background: white;
            border-radius: 8px;
            box-shadow: 0 10px 25px rgba(0,0,0,0.2);
            min-width: 150px;
            display: none;
            overflow: hidden;
        }
        
        .lang-dropdown.active {
            display: block;
        }
        
        .lang-dropdown a {
            display: block;
            padding: 10px 15px;
            color: var(--text-dark);
            text-decoration: none;
            font-size: 14px;
            transition: background 0.2s;
        }
        
        .lang-dropdown a:hover {
            background: var(--bg-light);
        }
        
        .lang-dropdown a.active {
            background: var(--primary-color);
            color: white;
        }
        
        /* 移动端菜单按钮 */
        .mobile-menu-btn {
            display: none;
            background: none;
            border: none;
            color: white;
            font-size: 24px;
            cursor: pointer;
            padding: 5px;
        }
        
        /* 移动端侧边栏 */
        .mobile-sidebar {
            position: fixed;
            top: 0;
            right: -300px;
            width: 300px;
            height: 100vh;
            background: white;
            z-index: 2000;
            transition: right 0.3s ease;
            box-shadow: -5px 0 20px rgba(0,0,0,0.2);
            overflow-y: auto;
        }
        
        .mobile-sidebar.active {
            right: 0;
        }
        
        .sidebar-header {
            background: var(--primary-color);
            color: white;
            padding: 20px;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        
        .close-sidebar {
            background: none;
            border: none;
            color: white;
            font-size: 24px;
            cursor: pointer;
        }
        
        .sidebar-nav {
            padding: 20px 0;
        }
        
        .sidebar-nav a {
            display: block;
            padding: 15px 20px;
            color: var(--text-dark);
            text-decoration: none;
            border-bottom: 1px solid var(--border-color);
            transition: background 0.2s;
        }
        
        .sidebar-nav a:hover {
            background: var(--bg-light);
        }
        
        .sidebar-lang {
            padding: 20px;
            border-top: 1px solid var(--border-color);
        }
        
        .sidebar-lang-title {
            font-weight: bold;
            margin-bottom: 10px;
            color: var(--text-dark);
        }
        
        .sidebar-lang-options {
            display: flex;
            flex-wrap: wrap;
            gap: 10px;
        }
        
        .sidebar-lang-options a {
            padding: 5px 12px;
            background: var(--bg-light);
            border-radius: 4px;
            text-decoration: none;
            color: var(--text-dark);
            font-size: 13px;
            transition: all 0.2s;
        }
        
        .sidebar-lang-options a:hover,
        .sidebar-lang-options a.active {
            background: var(--primary-color);
            color: white;
        }
        
        .overlay {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0,0,0,0.5);
            z-index: 1500;
            display: none;
        }
        
        .overlay.active {
            display: block;
        }
        
        /* Hero区域 */
        .hero {
            background: linear-gradient(135deg, var(--primary-color) 0%, #1e40af 100%);
            color: white;
            padding: 80px 0;
            text-align: center;
            position: relative;
            overflow: hidden;
        }
        
        .hero::before {
            content: '';
            position: absolute;
            top: -50%;
            right: -10%;
            width: 600px;
            height: 600px;
            background: rgba(255,255,255,0.05);
            border-radius: 50%;
        }
        
        .hero-content {
            position: relative;
            z-index: 1;
        }
        
        .hero h1 {
            font-size: 48px;
            margin-bottom: 20px;
            font-weight: 700;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
        }
        
        .hero-subtitle {
            font-size: 20px;
            margin-bottom: 30px;
            opacity: 0.95;
            max-width: 700px;
            margin-left: auto;
            margin-right: auto;
        }
        
        .version-badge {
            display: inline-block;
            background: var(--accent-color);
            color: white;
            padding: 8px 20px;
            border-radius: 20px;
            font-weight: bold;
            margin-bottom: 30px;
            font-size: 16px;
        }
        
        .hero-buttons {
            display: flex;
            gap: 15px;
            justify-content: center;
            flex-wrap: wrap;
        }
        
        .btn {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 15px 30px;
            border-radius: 8px;
            text-decoration: none;
            font-weight: 600;
            font-size: 16px;
            transition: all 0.3s;
            border: none;
            cursor: pointer;
        }
        
        .btn-primary {
            background: var(--accent-color);
            color: white;
            box-shadow: 0 4px 15px rgba(245, 158, 11, 0.4);
        }
        
        .btn-primary:hover {
            background: #d97706;
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(245, 158, 11, 0.5);
        }
        
        .btn-secondary {
            background: rgba(255,255,255,0.2);
            color: white;
            border: 2px solid rgba(255,255,255,0.3);
        }
        
        .btn-secondary:hover {
            background: rgba(255,255,255,0.3);
        }
        
        /* 核心功能 */
        .features {
            padding: 80px 0;
            background: var(--bg-white);
        }
        
        .section-title {
            text-align: center;
            font-size: 36px;
            margin-bottom: 15px;
            color: var(--text-dark);
        }
        
        .section-subtitle {
            text-align: center;
            color: var(--text-light);
            margin-bottom: 50px;
            font-size: 18px;
        }
        
        .features-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 30px;
        }
        
        .feature-card {
            background: var(--bg-light);
            padding: 30px;
            border-radius: 12px;
            border: 1px solid var(--border-color);
            transition: all 0.3s;
        }
        
        .feature-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 30px rgba(0,0,0,0.1);
            border-color: var(--primary-color);
        }
        
        .feature-icon {
            width: 60px;
            height: 60px;
            background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-size: 28px;
            margin-bottom: 20px;
        }
        
        .feature-card h3 {
            font-size: 20px;
            margin-bottom: 10px;
            color: var(--text-dark);
        }
        
        .feature-card p {
            color: var(--text-light);
            line-height: 1.6;
        }
        
        /* 下载模块 */
        .download-section {
            padding: 80px 0;
            background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
        }
        
        .download-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 30px;
            margin-top: 50px;
        }
        
        .download-card {
            background: white;
            border-radius: 16px;
            padding: 40px 30px;
            text-align: center;
            box-shadow: 0 4px 20px rgba(0,0,0,0.08);
            transition: all 0.3s;
            border: 2px solid transparent;
        }
        
        .download-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 30px rgba(0,0,0,0.12);
            border-color: var(--primary-color);
        }
        
        .download-icon {
            width: 80px;
            height: 80px;
            margin: 0 auto 20px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 36px;
        }
        
        .quark-icon { background: #e0f2fe; color: #0284c7; }
        .baidu-icon { background: #fef3c7; color: #d97706; }
        .xunlei-icon { background: #dbeafe; color: #2563eb; }
        
        .download-card h3 {
            font-size: 22px;
            margin-bottom: 10px;
            color: var(--text-dark);
        }
        
        .download-card p {
            color: var(--text-light);
            margin-bottom: 20px;
            font-size: 14px;
        }
        
        .download-btn {
            display: inline-block;
            width: 100%;
            padding: 15px;
            border-radius: 8px;
            text-decoration: none;
            font-weight: 600;
            color: white;
            transition: all 0.3s;
        }
        
        .quark-btn { background: #0284c7; }
        .quark-btn:hover { background: #0369a1; }
        .baidu-btn { background: #d97706; }
        .baidu-btn:hover { background: #b45309; }
        .xunlei-btn { background: #2563eb; }
        .xunlei-btn:hover { background: #1d4ed8; }
        
        .version-info {
            margin-top: 40px;
            background: white;
            padding: 30px;
            border-radius: 12px;
            box-shadow: 0 2px 10px rgba(0,0,0,0.05);
        }
        
        .version-info h3 {
            margin-bottom: 20px;
            color: var(--text-dark);
        }
        
        .version-info ul {
            list-style: none;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 10px;
        }
        
        .version-info li {
            padding: 8px 0;
            color: var(--text-light);
            display: flex;
            align-items: center;
            gap: 8px;
        }
        
        .version-info li::before {
            content: '✓';
            color: var(--secondary-color);
            font-weight: bold;
        }
        
        /* 适用场景 */
        .scenarios {
            padding: 80px 0;
            background: var(--bg-white);
        }
        
        .scenarios-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 25px;
            margin-top: 50px;
        }
        
        .scenario-card {
            position: relative;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            padding: 30px;
            border-radius: 12px;
            color: white;
            overflow: hidden;
        }
        
        .scenario-card:nth-child(2) {
            background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
        }
        
        .scenario-card:nth-child(3) {
            background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
        }
        
        .scenario-card:nth-child(4) {
            background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
        }
        
        .scenario-card:nth-child(5) {
            background: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
        }
        
        .scenario-card:nth-child(6) {
            background: linear-gradient(135deg, #30cfd0 0%, #330867 100%);
        }
        
        .scenario-icon {
            font-size: 40px;
            margin-bottom: 15px;
            opacity: 0.9;
        }
        
        .scenario-card h3 {
            font-size: 18px;
            margin-bottom: 10px;
        }
        
        .scenario-card p {
            font-size: 14px;
            opacity: 0.95;
            line-height: 1.5;
        }
        
        /* 系统要求 */
        .requirements {
            padding: 80px 0;
            background: var(--bg-light);
        }
        
        .requirements-content {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 50px;
            align-items: center;
            margin-top: 50px;
        }
        
        .requirements-info {
            background: white;
            padding: 40px;
            border-radius: 12px;
            box-shadow: 0 4px 20px rgba(0,0,0,0.08);
        }
        
        .requirements-info h3 {
            margin-bottom: 20px;
            color: var(--text-dark);
            font-size: 24px;
        }
        
        .req-item {
            display: flex;
            justify-content: space-between;
            padding: 15px 0;
            border-bottom: 1px solid var(--border-color);
        }
        
        .req-item:last-child {
            border-bottom: none;
        }
        
        .req-label {
            font-weight: 600;
            color: var(--text-dark);
        }
        
        .req-value {
            color: var(--text-light);
        }
        
        .requirements-image {
            text-align: center;
        }
        
        .system-icons {
            display: flex;
            justify-content: center;
            gap: 30px;
            flex-wrap: wrap;
        }
        
        .system-icon {
            width: 100px;
            height: 100px;
            background: white;
            border-radius: 20px;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            box-shadow: 0 4px 15px rgba(0,0,0,0.1);
            font-size: 40px;
        }
        
        .system-icon span {
            font-size: 12px;
            margin-top: 5px;
            color: var(--text-light);
        }
        
        /* 使用教程 */
        .tutorial {
            padding: 80px 0;
            background: var(--bg-white);
        }
        
        .tutorial-steps {
            display: flex;
            justify-content: space-between;
            margin-top: 50px;
            position: relative;
        }
        
        .tutorial-steps::before {
            content: '';
            position: absolute;
            top: 30px;
            left: 10%;
            right: 10%;
            height: 4px;
            background: var(--border-color);
            z-index: 0;
        }
        
        .tutorial-step {
            position: relative;
            z-index: 1;
            text-align: center;
            width: 20%;
        }
        
        .step-number {
            width: 60px;
            height: 60px;
            background: var(--primary-color);
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 24px;
            font-weight: bold;
            margin: 0 auto 15px;
            border: 4px solid white;
            box-shadow: 0 2px 10px rgba(0,0,0,0.1);
        }
        
        .tutorial-step h4 {
            margin-bottom: 10px;
            color: var(--text-dark);
        }
        
        .tutorial-step p {
            font-size: 14px;
            color: var(--text-light);
            padding: 0 10px;
        }
        
        .tutorial-content {
            margin-top: 60px;
            background: var(--bg-light);
            padding: 40px;
            border-radius: 12px;
        }
        
        .tutorial-detail {
            display: none;
        }
        
        .tutorial-detail.active {
            display: block;
        }
        
        .tutorial-detail h4 {
            color: var(--primary-color);
            margin-bottom: 15px;
            font-size: 20px;
        }
        
        .tutorial-detail p {
            color: var(--text-light);
            line-height: 1.8;
            margin-bottom: 15px;
        }
        
        .tutorial-detail code {
            background: #e5e7eb;
            padding: 2px 6px;
            border-radius: 4px;
            font-family: monospace;
            color: var(--text-dark);
        }
        
        /* 常见问题 */
        .faq {
            padding: 80px 0;
            background: var(--bg-light);
        }
        
        .faq-list {
            max-width: 800px;
            margin: 50px auto 0;
        }
        
        .faq-item {
            background: white;
            margin-bottom: 15px;
            border-radius: 8px;
            overflow: hidden;
            box-shadow: 0 2px 8px rgba(0,0,0,0.05);
        }
        
        .faq-question {
            padding: 20px 25px;
            cursor: pointer;
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-weight: 600;
            color: var(--text-dark);
            transition: background 0.2s;
        }
        
        .faq-question:hover {
            background: var(--bg-light);
        }
        
        .faq-question::after {
            content: '+';
            font-size: 24px;
            color: var(--primary-color);
            transition: transform 0.3s;
        }
        
        .faq-item.active .faq-question::after {
            transform: rotate(45deg);
        }
        
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease;
        }
        
        .faq-item.active .faq-answer {
            max-height: 500px;
        }
        
        .faq-answer-content {
            padding: 0 25px 20px;
            color: var(--text-light);
            line-height: 1.8;
        }
        
        /* 友情链接 */
        .links {
            padding: 60px 0;
            background: var(--bg-white);
        }
        
        .links-grid {
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            gap: 20px;
            margin-top: 30px;
        }
        
        .link-item {
            padding: 10px 20px;
            background: var(--bg-light);
            border-radius: 6px;
            text-decoration: none;
            color: var(--text-dark);
            transition: all 0.2s;
            border: 1px solid var(--border-color);
        }
        
        .link-item:hover {
            background: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }
        
        /* 底部 */
        footer {
            background: var(--text-dark);
            color: white;
            padding: 40px 0 100px;
            text-align: center;
        }
        
        .footer-content {
            margin-bottom: 20px;
        }
        
        .footer-links {
            display: flex;
            justify-content: center;
            gap: 30px;
            margin-bottom: 20px;
            flex-wrap: wrap;
        }
        
        .footer-links a {
            color: rgba(255,255,255,0.8);
            text-decoration: none;
            transition: color 0.2s;
        }
        
        .footer-links a:hover {
            color: white;
        }
        
        .copyright {
            color: rgba(255,255,255,0.6);
            font-size: 14px;
            line-height: 1.8;
        }
        
        .disclaimer {
            margin-top: 20px;
            padding: 15px;
            background: rgba(255,255,255,0.1);
            border-radius: 8px;
            font-size: 13px;
            color: rgba(255,255,255,0.8);
            max-width: 800px;
            margin-left: auto;
            margin-right: auto;
        }
        
        /* 悬浮广告模块 */
        .floating-bar {
            position: fixed;
            bottom: 0;
            left: 0;
            right: 0;
            background: linear-gradient(90deg, var(--primary-color) 0%, var(--primary-dark) 100%);
            color: white;
            padding: 15px 20px;
            z-index: 1000;
            display: flex;
            justify-content: space-between;
            align-items: center;
            box-shadow: 0 -4px 20px rgba(0,0,0,0.2);
        }
        
        .floating-content {
            max-width: 1200px;
            margin: 0 auto;
            width: 100%;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        
        .floating-text {
            display: flex;
            align-items: center;
            gap: 15px;
        }
        
        .floating-text strong {
            font-size: 18px;
        }
        
        .floating-text span {
            opacity: 0.9;
            font-size: 14px;
        }
        
        .floating-btn {
            background: var(--accent-color);
            color: white;
            padding: 12px 30px;
            border-radius: 6px;
            text-decoration: none;
            font-weight: 600;
            transition: all 0.3s;
            white-space: nowrap;
        }
        
        .floating-btn:hover {
            background: #d97706;
            transform: scale(1.05);
        }
        
        /* 返回顶部按钮 */
        .back-to-top {
            position: fixed;
            bottom: 80px;
            right: 30px;
            width: 50px;
            height: 50px;
            background: var(--primary-color);
            color: white;
            border: none;
            border-radius: 50%;
            cursor: pointer;
            font-size: 20px;
            z-index: 999;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s;
            box-shadow: 0 4px 15px rgba(0,0,0,0.3);
            display: flex;
            align-items: center;
            justify-content: center;
        }
        
        .back-to-top.visible {
            opacity: 1;
            visibility: visible;
        }
        
        .back-to-top:hover {
            background: var(--primary-dark);
            transform: translateY(-3px);
        }
        
        /* 响应式设计 */
        @media (max-width: 768px) {
            .desktop-nav {
                display: none;
            }
            
            .mobile-menu-btn {
                display: block;
            }
            
            .hero h1 {
                font-size: 32px;
            }
            
            .hero-subtitle {
                font-size: 16px;
            }
            
            .requirements-content {
                grid-template-columns: 1fr;
            }
            
            .tutorial-steps {
                flex-direction: column;
                gap: 30px;
            }
            
            .tutorial-steps::before {
                display: none;
            }
            
            .tutorial-step {
                width: 100%;
            }
            
            .floating-content {
                flex-direction: column;
                gap: 10px;
                text-align: center;
            }
            
            .floating-text {
                flex-direction: column;
                gap: 5px;
            }
            
            .features-grid,
            .download-grid,
            .scenarios-grid {
                grid-template-columns: 1fr;
            }
            
            .back-to-top {
                bottom: 100px;
                right: 20px;
            }
        }
        
        /* 平滑滚动 */
        html {
            scroll-behavior: smooth;
        }
        
        /* 高亮文本 */
        .highlight {
            color: var(--primary-color);
            font-weight: 600;
        }
        
        /* 标签 */
        .tag {
            display: inline-block;
            padding: 4px 12px;
            background: var(--primary-color);
            color: white;
            border-radius: 20px;
            font-size: 12px;
            margin-right: 5px;
            margin-bottom: 5px;
        }
        
        .tag-success {
            background: var(--secondary-color);
        }
        
        .tag-warning {
            background: var(--accent-color);
        }