/* 全局基础重置与变量 */
        * { margin: 0; padding: 0; box-sizing: border-box; }
        body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Microsoft YaHei", sans-serif; background: #f8fafc; color: #1e293b; line-height: 1.6; }
        .container { max-width: 1140px; margin: 0 auto; padding: 0 20px; }
        a { text-decoration: none; transition: all 0.25s ease; }

        /* ========= 1. 现代化导航栏优化 ========= */
        .header { 
            background: rgba(255, 255, 255, 0.88); 
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            padding: 16px 0; 
            border-bottom: 1px solid rgba(226, 232, 240, 0.8); 
            position: sticky; 
            top: 0; 
            z-index: 1000; 
            box-shadow: 0 4px 20px rgba(0, 0, 0, 0.03);
        }
        .nav-flex { display: flex; align-items: center; justify-content: space-between; }
        .logo { display: flex; align-items: center; font-size: 22px; font-weight: 800; color: #0088cb; gap: 10px; }
        .logo img { width: 32px; height: 32px; transition: transform 0.3s ease; }
        .logo:hover img { transform: rotate(12deg) scale(1.05); }
        
        .nav-right-box { display: flex; align-items: center; gap: 32px; }
        .nav-list { display: flex; list-style: none; gap: 32px; align-items: center; }
        .nav-list a { color: #475569; font-weight: 500; font-size: 15px; position: relative; padding: 4px 0; }
        .nav-list a:hover, .nav-list a.active { color: #0088cb; font-weight: 600; }
        .nav-list a::after {
            content: ''; position: absolute; bottom: 0; left: 0; width: 0; height: 2px;
            background-color: #0088cb; transition: width 0.3s ease; border-radius: 2px;
        }
        .nav-list a:hover::after, .nav-list a.active::after { width: 100%; }

        .nav-btn-cta {
            background: #0088cb; color: #ffffff !important; padding: 9px 22px;
            border-radius: 50px; font-size: 14px; font-weight: 600;
            box-shadow: 0 4px 14px rgba(0, 136, 203, 0.25); transition: all 0.25s ease;
        }
        .nav-btn-cta:hover { background: #0077b3; transform: translateY(-1px); box-shadow: 0 6px 20px rgba(0, 136, 203, 0.35); }
        .nav-btn-cta::after { display: none !important; }

        /* ========= 2. 主下载横幅区域 ========= */
        .download-wrapper { padding: 60px 0; background: #ffffff; border-bottom: 1px solid #f1f5f9; }
        .download-flex { display: flex; align-items: center; gap: 50px; }
        .download-media { flex: 1; text-align: center; }
        .download-media img { max-width: 100%; height: auto; border-radius: 12px; box-shadow: 0 12px 30px rgba(0,0,0,0.08); }
        .download-content { flex: 1; }
        .download-content h1 { font-size: 34px; font-weight: 800; color: #0f172a; margin-bottom: 16px; line-height: 1.25; }
        .download-content p { color: #475569; font-size: 16px; margin-bottom: 28px; line-height: 1.7; }
        .btn-group-vertical { display: flex; flex-direction: column; gap: 12px; align-items: flex-start; }
        .btn-dl { 
            display: inline-flex; align-items: center; justify-content: center; gap: 12px;
            padding: 16px 36px; background: #0088cb; color: #fff !important;
            border-radius: 50px; font-weight: 700; font-size: 17px;
            box-shadow: 0 8px 20px rgba(0, 136, 203, 0.3); transition: all 0.25s ease; cursor: pointer;
        }
        .btn-dl:hover { background: #0f172a; transform: translateY(-2px); box-shadow: 0 12px 25px rgba(15, 23, 42, 0.25); }
        .btn-dl img { width: 22px; height: 22px; filter: brightness(0) invert(1); }
        .sys-info { color: #94a3b8; font-size: 13px; margin-left: 8px; }

        /* ========= 3. 下方区域重构：PC 核心优势区 (SEO 优化) ========= */
        .features-section { padding: 70px 0; background: #f8fafc; }
        .section-title { text-align: center; font-size: 28px; font-weight: 800; color: #0f172a; margin-bottom: 40px; }
        .features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 24px; }
        .feature-card { background: #ffffff; padding: 28px; border-radius: 16px; border: 1px solid #f1f5f9; box-shadow: 0 4px 12px rgba(0,0,0,0.02); }
        .feature-card h3 { font-size: 18px; color: #0088cb; margin-bottom: 10px; display: flex; align-items: center; gap: 8px; }
        .feature-card p { color: #64748b; font-size: 14px; line-height: 1.6; }

        /* ========= 4. 下方区域重构：6步安装教程卡片 ========= */
        .tutorial-section { padding: 70px 0; background: #ffffff; border-top: 1px solid #f1f5f9; }
        .tutorial-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; margin-top: 10px; }
        .tutorial-step { background: #f8fafc; border-radius: 16px; padding: 28px; border: 1px solid #f1f5f9; position: relative; transition: all 0.3s ease; }
        .tutorial-step:hover { transform: translateY(-4px); box-shadow: 0 12px 25px rgba(0,0,0,0.05); background: #ffffff; }
        .step-header { display: flex; align-items: center; gap: 12px; margin-bottom: 12px; }
        .step-num { 
            background: linear-gradient(135deg, #0088cb 0%, #006699 100%); color: #fff;
            font-weight: 800; width: 34px; height: 34px; line-height: 34px;
            text-align: center; border-radius: 10px; font-size: 15px; flex-shrink: 0;
        }
        .tutorial-step h3 { font-size: 18px; color: #0f172a; }
        .tutorial-step p { color: #64748b; font-size: 14px; margin-bottom: 14px; line-height: 1.6; }
        .badge { display: inline-block; background: #e0f2fe; color: #0369a1; border-radius: 20px; padding: 3px 12px; font-size: 12px; font-weight: 600; }

        /* ========= 5. 下方区域重构：常见问题手风琴区 ========= */
        .faq-section { padding: 70px 0; background: #f8fafc; border-top: 1px solid #f1f5f9; }
        .faq-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; margin-top: 10px; }
        .faq-card { background: #ffffff; padding: 28px; border-radius: 16px; border: 1px solid #f1f5f9; box-shadow: 0 4px 12px rgba(0,0,0,0.02); }
        .faq-card h4 { font-size: 17px; color: #0f172a; margin-bottom: 10px; display: flex; align-items: center; gap: 8px; }
        .faq-card p { color: #64748b; font-size: 14px; line-height: 1.65; }

        /* 页脚 */
        footer { text-align: center; padding: 35px 0; color: #94a3b8; font-size: 14px; border-top: 1px solid #f1f5f9; background: #ffffff; }

        /* 响应式断点 */
        @media (max-width: 992px) {
            .download-flex { flex-direction: column; text-align: center; gap: 30px; }
            .btn-group-vertical { align-items: center; }
            .tutorial-grid, .faq-grid { grid-template-columns: repeat(2, 1fr); }
        }
        @media (max-width: 700px) {
            .nav-list { display: none; }
            .tutorial-grid, .faq-grid { grid-template-columns: 1fr; }
            .download-wrapper, .features-section, .tutorial-section, .faq-section { padding: 40px 0; }
        }