* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        :root {
            --primary-color: #0066cc;
            --primary-dark: #0052a3;
            --secondary-color: #f0f2f5;
            --text-dark: #333333;
            --text-light: #666666;
            --border-color: #e8e8e8;
            --success-color: #52c41a;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
            color: var(--text-dark);
            line-height: 1.6;
            background-color: #ffffff;
        }

        /* ========== 通用样式 ========== */
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }

        .btn {
            display: inline-block;
            padding: 12px 28px;
            border-radius: 4px;
            text-decoration: none;
            font-size: 16px;
            font-weight: 500;
            transition: all 0.3s ease;
            border: none;
            cursor: pointer;
        }

        .btn-primary {
            background-color: var(--primary-color);
            color: #ffffff;
        }

        .btn-primary:hover {
            background-color: var(--primary-dark);
            transform: translateY(-2px);
            box-shadow: 0 4px 12px rgba(0, 102, 204, 0.3);
        }

        .btn-secondary {
            background-color: var(--secondary-color);
            color: var(--text-dark);
            border: 1px solid var(--border-color);
        }

        .btn-secondary:hover {
            background-color: #e8e8e8;
        }

        /* ========== 顶部导航 ========== */
        header {
            background-color: #ffffff;
            border-bottom: 1px solid var(--border-color);
            position: sticky;
            top: 0;
            z-index: 100;
            box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
        }

        .header-content {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 16px 0;
        }

        .logo {
            font-size: 24px;
            font-weight: bold;
            color: var(--primary-color);
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .logo-icon {
            width: 32px;
            height: 32px;
            background: linear-gradient(135deg, #0066cc, #0052a3);
            border-radius: 4px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-weight: bold;
        }

        nav {
            display: flex;
            gap: 30px;
            align-items: center;
        }

        nav a {
            color: var(--text-dark);
            text-decoration: none;
            font-size: 15px;
            transition: color 0.3s;
        }

        nav a:hover {
            color: var(--primary-color);
        }

        .nav-right {
            display: flex;
            gap: 16px;
            align-items: center;
        }

        /* 语言切换 */
        .language-selector {
            position: relative;
        }

        .lang-btn {
            background: none;
            border: none;
            cursor: pointer;
            font-size: 14px;
            color: var(--text-light);
            display: flex;
            align-items: center;
            gap: 4px;
            padding: 4px 8px;
        }

        .lang-btn:hover {
            color: var(--primary-color);
        }

        .lang-dropdown {
            display: none;
            position: absolute;
            top: 100%;
            right: 0;
            background: white;
            border: 1px solid var(--border-color);
            border-radius: 4px;
            box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
            min-width: 120px;
            z-index: 1000;
        }

        .lang-dropdown.active {
            display: block;
        }

        .lang-option {
            display: block;
            width: 100%;
            padding: 10px 16px;
            border: none;
            background: none;
            text-align: left;
            cursor: pointer;
            font-size: 14px;
            color: var(--text-dark);
            transition: background-color 0.2s;
        }

        .lang-option:hover {
            background-color: var(--secondary-color);
        }

        .lang-option.active {
            color: var(--primary-color);
            font-weight: 500;
        }

        /* 菜单按钮 */
        .menu-btn {
            display: none;
            background: none;
            border: none;
            font-size: 24px;
            cursor: pointer;
            color: var(--text-dark);
        }

        .menu-btn:hover {
            color: var(--primary-color);
        }

        /* 侧边菜单 */
        .side-menu {
            display: none;
            position: fixed;
            right: -300px;
            top: 0;
            width: 300px;
            height: 100vh;
            background: white;
            box-shadow: -4px 0 12px rgba(0, 0, 0, 0.15);
            z-index: 999;
            transition: right 0.3s ease;
            overflow-y: auto;
            padding: 20px;
        }

        .side-menu.active {
            right: 0;
        }

        .side-menu-close {
            background: none;
            border: none;
            font-size: 24px;
            cursor: pointer;
            float: right;
            color: var(--text-dark);
        }

        .side-menu nav {
            display: flex;
            flex-direction: column;
            gap: 20px;
            margin-top: 30px;
            clear: both;
        }

        .side-menu nav a {
            display: block;
            color: var(--text-dark);
            text-decoration: none;
            font-size: 16px;
            padding: 10px 0;
            border-bottom: 1px solid var(--border-color);
        }

        /* ========== 英雄区域 ========== */
        .hero {
            background: linear-gradient(135deg, #0066cc 0%, #0052a3 100%);
            color: white;
            padding: 80px 20px;
            text-align: center;
        }

        .hero-content h1 {
            font-size: 48px;
            margin-bottom: 20px;
            line-height: 1.2;
        }

        .hero-content p {
            font-size: 20px;
            margin-bottom: 40px;
            opacity: 0.95;
        }

        .hero-buttons {
            display: flex;
            gap: 16px;
            justify-content: center;
            flex-wrap: wrap;
        }

        .btn-download {
            background-color: #52c41a;
            color: white;
            padding: 14px 32px;
            font-size: 18px;
        }

        .btn-download:hover {
            background-color: #45a517;
        }

        .btn-learn {
            background-color: rgba(255, 255, 255, 0.2);
            color: white;
            border: 2px solid white;
            padding: 12px 30px;
        }

        .btn-learn:hover {
            background-color: rgba(255, 255, 255, 0.3);
        }

        /* ========== 功能区域 ========== */
        .features {
            padding: 80px 20px;
            background-color: var(--secondary-color);
        }

        .section-title {
            font-size: 36px;
            text-align: center;
            margin-bottom: 50px;
            color: var(--text-dark);
        }

        .features-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 30px;
        }

        .feature-card {
            background: white;
            padding: 30px;
            border-radius: 8px;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
            transition: transform 0.3s, box-shadow 0.3s;
        }

        .feature-card:hover {
            transform: translateY(-4px);
            box-shadow: 0 8px 16px rgba(0, 0, 0, 0.12);
        }

        .feature-icon {
            font-size: 40px;
            margin-bottom: 16px;
        }

        .feature-card h3 {
            font-size: 20px;
            margin-bottom: 12px;
            color: var(--text-dark);
        }

        .feature-card p {
            color: var(--text-light);
            font-size: 14px;
            line-height: 1.8;
        }

        /* ========== 下载模块 ========== */
        .download-section {
            padding: 80px 20px;
            background: white;
        }

        .download-container {
            max-width: 800px;
            margin: 0 auto;
        }

        .download-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 30px;
            margin-top: 40px;
        }

        .download-card {
            background: var(--secondary-color);
            padding: 40px;
            border-radius: 8px;
            text-align: center;
            border: 2px solid var(--border-color);
            transition: all 0.3s;
        }

        .download-card:hover {
            border-color: var(--primary-color);
            box-shadow: 0 4px 12px rgba(0, 102, 204, 0.15);
        }

        .download-card h3 {
            font-size: 24px;
            margin-bottom: 20px;
            color: var(--text-dark);
        }

        .download-card .platform-info {
            font-size: 14px;
            color: var(--text-light);
            margin-bottom: 20px;
        }

        .download-links {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .download-link {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            padding: 12px 20px;
            background: white;
            border: 1px solid var(--border-color);
            border-radius: 4px;
            text-decoration: none;
            color: var(--primary-color);
            font-weight: 500;
            transition: all 0.3s;
        }

        .download-link:hover {
            background: var(--primary-color);
            color: white;
            border-color: var(--primary-color);
        }

        /* ========== 应用场景 ========== */
        .scenarios {
            padding: 80px 20px;
            background: var(--secondary-color);
        }

        .scenarios-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 30px;
            margin-top: 40px;
        }

        .scenario-item {
            background: white;
            padding: 30px;
            border-radius: 8px;
            text-align: center;
        }

        .scenario-item h3 {
            font-size: 18px;
            margin-bottom: 12px;
            color: var(--text-dark);
        }

        .scenario-item p {
            color: var(--text-light);
            font-size: 14px;
        }

        /* ========== 系统要求 ========== */
        .requirements {
            padding: 80px 20px;
            background: white;
        }

        .requirements-content {
            max-width: 900px;
            margin: 0 auto;
        }

        .requirements-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 30px;
            margin-top: 40px;
        }

        .requirement-box {
            background: var(--secondary-color);
            padding: 30px;
            border-radius: 8px;
            border-left: 4px solid var(--primary-color);
        }

        .requirement-box h3 {
            font-size: 18px;
            margin-bottom: 16px;
            color: var(--text-dark);
        }

        .requirement-box ul {
            list-style: none;
            padding: 0;
        }

        .requirement-box li {
            padding: 8px 0;
            color: var(--text-light);
            font-size: 14px;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .requirement-box li:before {
            content: "✓";
            color: var(--success-color);
            font-weight: bold;
        }

        /* ========== 常见问题 ========== */
        .faq {
            padding: 80px 20px;
            background: var(--secondary-color);
        }

        .faq-content {
            max-width: 800px;
            margin: 0 auto;
        }

        .faq-item {
            background: white;
            margin-bottom: 16px;
            border-radius: 4px;
            overflow: hidden;
        }

        .faq-question {
            padding: 20px;
            background: white;
            border: 1px solid var(--border-color);
            cursor: pointer;
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-weight: 500;
            transition: background-color 0.3s;
        }

        .faq-question:hover {
            background-color: var(--secondary-color);
        }

        .faq-question.active {
            background-color: var(--primary-color);
            color: white;
        }

        .faq-toggle {
            font-size: 20px;
            transition: transform 0.3s;
        }

        .faq-question.active .faq-toggle {
            transform: rotate(180deg);
        }

        .faq-answer {
            display: none;
            padding: 20px;
            background: #fafafa;
            color: var(--text-light);
            font-size: 14px;
            line-height: 1.8;
            border-top: 1px solid var(--border-color);
        }

        .faq-answer.active {
            display: block;
        }

        /* ========== 友情链接 ========== */
        .links {
            padding: 60px 20px;
            background: white;
            border-top: 1px solid var(--border-color);
        }

        .links-content {
            max-width: 1200px;
            margin: 0 auto;
        }

        .links-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 20px;
            margin-top: 30px;
        }

        .link-item {
            text-align: center;
        }

        .link-item a {
            color: var(--primary-color);
            text-decoration: none;
            font-size: 14px;
            transition: color 0.3s;
        }

        .link-item a:hover {
            color: var(--primary-dark);
            text-decoration: underline;
        }

        /* ========== 底部 ========== */
        footer {
            background: #2c3e50;
            color: #ecf0f1;
            padding: 40px 20px 20px;
            font-size: 14px;
        }

        .footer-content {
            max-width: 1200px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 30px;
            margin-bottom: 30px;
        }

        .footer-section h4 {
            margin-bottom: 16px;
            font-size: 16px;
        }

        .footer-section a {
            display: block;
            color: #bdc3c7;
            text-decoration: none;
            margin-bottom: 8px;
            transition: color 0.3s;
        }

        .footer-section a:hover {
            color: #ecf0f1;
        }

        .footer-bottom {
            border-top: 1px solid #34495e;
            padding-top: 20px;
            text-align: center;
            color: #95a5a6;
        }

        /* ========== 悬浮广告 ========== */
        .floating-ad {
            position: fixed;
            bottom: 20px;
            left: 20px;
            background: white;
            border-radius: 8px;
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
            padding: 16px 20px;
            z-index: 99;
            display: flex;
            align-items: center;
            gap: 12px;
            animation: slideInLeft 0.5s ease;
        }

        @keyframes slideInLeft {
            from {
                transform: translateX(-400px);
                opacity: 0;
            }
            to {
                transform: translateX(0);
                opacity: 1;
            }
        }

        .floating-ad-text {
            font-size: 14px;
            color: var(--text-dark);
            font-weight: 500;
        }

        .floating-ad-link {
            background: var(--primary-color);
            color: white;
            padding: 8px 16px;
            border-radius: 4px;
            text-decoration: none;
            font-size: 14px;
            font-weight: 500;
            white-space: nowrap;
            transition: background-color 0.3s;
        }

        .floating-ad-link:hover {
            background: var(--primary-dark);
        }

        .floating-ad-close {
            background: none;
            border: none;
            cursor: pointer;
            color: var(--text-light);
            font-size: 18px;
            padding: 0;
            margin-left: 8px;
        }

        /* ========== 返回顶部 ========== */
        .back-to-top {
            position: fixed;
            bottom: 20px;
            right: 20px;
            width: 50px;
            height: 50px;
            background: var(--primary-color);
            color: white;
            border: none;
            border-radius: 50%;
            cursor: pointer;
            font-size: 24px;
            display: none;
            align-items: center;
            justify-content: center;
            z-index: 98;
            transition: all 0.3s;
            box-shadow: 0 4px 12px rgba(0, 102, 204, 0.3);
        }

        .back-to-top.show {
            display: flex;
        }

        .back-to-top:hover {
            background: var(--primary-dark);
            transform: translateY(-4px);
            box-shadow: 0 6px 16px rgba(0, 102, 204, 0.4);
        }

        /* ========== 响应式设计 ========== */
        @media (max-width: 768px) {
            .menu-btn {
                display: block;
            }

            nav {
                display: none;
            }

            .side-menu {
                display: block;
            }

            .hero-content h1 {
                font-size: 32px;
            }

            .hero-content p {
                font-size: 16px;
            }

            .hero-buttons {
                flex-direction: column;
                align-items: center;
            }

            .btn {
                width: 100%;
                max-width: 300px;
            }

            .section-title {
                font-size: 28px;
            }

            .features-grid,
            .download-grid,
            .scenarios-grid,
            .requirements-grid {
                grid-template-columns: 1fr;
            }

            .floating-ad {
                left: 10px;
                right: 10px;
                bottom: 80px;
                flex-direction: column;
                text-align: center;
            }

            .back-to-top {
                width: 45px;
                height: 45px;
                font-size: 20px;
                bottom: 10px;
                right: 10px;
            }

            .footer-content {
                grid-template-columns: 1fr;
                gap: 20px;
            }
        }

        @media (max-width: 480px) {
            .hero-content h1 {
                font-size: 24px;
            }

            .hero-content p {
                font-size: 14px;
            }

            .section-title {
                font-size: 24px;
            }

            .btn {
                padding: 10px 20px;
                font-size: 14px;
            }
        }