body { 
            font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif; 
            line-height: 1.6; 
            color: var(--text-main); 
            background-color: #fff; 
            overflow-x: hidden;
            -webkit-font-smoothing: antialiased;
        }

        .container { max-width: 1140px; margin: 0 auto; padding: 0 24px; }

        /* --- 1. 导航栏 --- */
        .header { 
            background: var(--dark-glass); 
            backdrop-filter: blur(15px); 
            -webkit-backdrop-filter: blur(15px); 
            padding: 12px 0; 
            position: fixed; 
            top: 0; 
            width: 100%; 
            z-index: 1000; 
            border-bottom: 1px solid rgba(255, 255, 255, 0.1); 
        }
        .nav { display: flex; justify-content: space-between; align-items: center; }
        .logo-group { display: flex; align-items: center; gap: 12px; text-decoration: none; }
        .logo-img { 
            width: 38px; height: 38px; 
            background: linear-gradient(135deg, var(--brand-red), var(--brand-orange)); 
            border-radius: 10px; 
            display: flex; align-items: center; justify-content: center; 
            color: white; font-weight: 900; font-size: 20px; 
            overflow: hidden;
        }
        .logo-img img { width: 100%; height: 100%; object-fit: cover; }
        .logo-text { font-size: 24px; font-weight: 800; color: #fff; letter-spacing: 1px; }
        .nav-btn { background: var(--brand-red); color: white; padding: 8px 18px; border-radius: 50px; text-decoration: none; font-size: 14px; font-weight: bold; transition: var(--transition); }
        .nav-btn:hover { transform: translateY(-2px); box-shadow: 0 5px 15px rgba(255, 40, 73, 0.4); }

        /* --- 2. Hero 区域 --- */
        .hero { 
            padding: 180px 0 120px; text-align: center; 
            background: linear-gradient(135deg, #2b2b2b 0%, #000000 100%); 
            color: white; position: relative; 
        }
        .hero h1 { font-size: clamp(2.2rem, 6vw, 3.5rem); margin-bottom: 20px; background: linear-gradient(to right, #fff, var(--brand-gold)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; font-weight: 800; }
        .hero p { font-size: 1.2rem; color: rgba(255, 255, 255, 0.7); margin-bottom: 45px; }
        
        .hero-download-btn { 
            display: inline-block;
            background: var(--brand-red); 
            color: white; 
            padding: 16px 40px; 
            border-radius: 14px; 
            text-decoration: none; 
            font-weight: 800; 
            transition: var(--transition);
            box-shadow: 0 10px 20px rgba(255, 40, 73, 0.3);
        }
        .hero-download-btn:hover { transform: translateY(-3px); box-shadow: 0 15px 30px rgba(255, 40, 73, 0.4); }

        .hero-wave { position: absolute; bottom: -1px; left: 0; width: 100%; line-height: 0; }
        .hero-wave svg { width: 100%; height: 80px; display: block; }

        /* --- 公共标题样式 --- */
        .section-header { text-align: center; margin-bottom: 60px; }
        .section-header h2 { font-size: 2.2rem; position: relative; display: inline-block; padding-bottom: 15px; }
        .section-header h2::after { content: ''; position: absolute; bottom: 0; left: 50%; width: 50px; height: 4px; background: var(--brand-red); transform: translateX(-50%); border-radius: 2px; }

        /* --- 3. 为什么选择我们 --- */
        .features { padding: 100px 0; background-color: var(--bg-light); }
        .features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 30px; }
        .feature-card { background: #fff; padding: 40px 30px; border-radius: 24px; text-align: center; transition: var(--transition); border: 1px solid #eee; display: flex; flex-direction: column; align-items: center; }
        .icon-box { width: 70px; height: 70px; background: #fff1f2; border-radius: 18px; display: flex; align-items: center; justify-content: center; font-size: 30px; margin-bottom: 20px; flex-shrink: 0; }
        .feature-card:hover { transform: translateY(-10px); box-shadow: 0 20px 40px rgba(255, 40, 73, 0.1); border-color: var(--brand-red); }
        .feature-info h3 { margin-bottom: 10px; font-size: 1.2rem; }
        .feature-info p { color: var(--text-muted); font-size: 0.95rem; }

        /* --- 4. 新手教程 --- */
        .tutorial-section { padding: 100px 0; background-color: #fff; }
        .tutorial-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 20px; }
        .tutorial-item { text-align: center; padding: 30px; border-radius: 24px; display: flex; flex-direction: column; align-items: center; transition: var(--transition); }
        .step-blob { width: 65px; height: 65px; background: linear-gradient(135deg, var(--brand-red), var(--brand-orange)); color: white; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 26px; font-weight: 800; margin-bottom: 25px; flex-shrink: 0; }
        .tutorial-info h4 { margin-bottom: 10px; font-size: 1.1rem; }
        .tutorial-info p { color: var(--text-muted); font-size: 0.95rem; }

        /* --- 5. 常见问答 --- */
        .faq-section { padding: 100px 0; background-color: var(--bg-light); }
        .faq-container { max-width: 850px; margin: 0 auto; }
        .faq-item { background: #fff; border-radius: 18px; padding: 30px; margin-bottom: 15px; border: 1px solid #f0f0f0; }
        .faq-q { font-weight: 700; color: #333; font-size: 18px; margin-bottom: 12px; display: flex; align-items: center; gap: 10px; }
        .faq-q::before { content: 'Q'; color: var(--brand-red); font-size: 22px; font-style: italic; }
        .faq-a { color: var(--text-muted); font-size: 16px; line-height: 1.8; padding-left: 32px; border-left: 3px solid #fef0f0; }

        /* --- 6. 下载区域 & 滑动截图样式 (最终修正版) --- */
        .download-zone { 
            background: linear-gradient(135deg, var(--eye-care-start) 0%, var(--eye-care-end) 100%); 
            color: var(--text-main); 
            text-align: center; 
            padding: 100px 0 0 0; 
            overflow: hidden; 
        }
        .download-zone h2 { font-size: 2.6rem; margin-bottom: 15px; color: #2c3e50; }
        .download-zone p { opacity: 0.9; margin-bottom: 45px; font-size: 1.1rem; color: #555; }
        
        .btn-group { display: flex; justify-content: center; gap: 20px; margin-bottom: 60px; flex-wrap: wrap; }
        .download-btn-white { background: #fff; color: var(--brand-red); padding: 16px 40px; border-radius: 14px; text-decoration: none; font-weight: 800; transition: var(--transition); box-shadow: 0 4px 10px rgba(0,0,0,0.05); }
        .download-btn-white:hover { transform: translateY(-3px); box-shadow: 0 8px 20px rgba(0,0,0,0.1); }

        /* 滑动/网格容器 */
        .app-slider-container {
            width: 100%;
            margin: 0 auto;
            padding: 0 20px 60px;
            position: relative;
        }

        .app-slider {
            display: flex;
            gap: 20px;
            overflow-x: auto;
            scroll-snap-type: x mandatory;
            -webkit-overflow-scrolling: touch;
            padding: 20px 5px 50px 5px;
            scrollbar-width: none;
            /* 默认左对齐，电脑端会通过JS或CSS强制不换行显示全部 */
            justify-content: flex-start; 
        }

        .app-slider::-webkit-scrollbar {
            display: none;
        }

        .slide-item {
            flex: 0 0 auto;
            /* 默认宽度（移动端会覆盖） */
            width: 300px; 
            scroll-snap-align: center;
            background: #fff;
            border-radius: 24px;
            padding: 0; 
            box-shadow: 0 10px 25px rgba(0,0,0,0.08);
            transition: transform 0.3s ease;
            display: flex;
            flex-direction: column;
            align-items: center;
            overflow: hidden;
        }

        .slide-item:hover {
            transform: translateY(-5px);
            box-shadow: 0 15px 35px rgba(0,0,0,0.12);
        }

        .slide-item img {
            width: 300px;
            height: 600px;
            object-fit: cover;
            display: block;
            background-color: #f0f0f0;
        }

        .slide-caption {
            margin-top: 15px;
            font-size: 15px;
            color: #333333; 
            font-weight: 700;
            text-align: center;
            letter-spacing: 0.5px;
            width: 100%;
            padding-bottom: 5px;
        }

        .slider-indicator {
            text-align: center;
            color: #666;
            font-size: 13px;
            margin-top: -30px;
            margin-bottom: 20px;
            animation: pulse 2s infinite;
            user-select: none;
            font-weight: 600;
        }

        @keyframes pulse {
            0% { opacity: 0.4; }
            50% { opacity: 0.9; }
            100% { opacity: 0.4; }
        }

        .footer { background: #121212; color: #777; padding: 60px 0 40px; text-align: center; font-size: 0.9rem; }

        /* --- 关键：桌面端适配 (显示全部4张，不滑动) --- */
        @media (min-width: 1300px) {
            .app-slider {
                overflow-x: visible; /* 允许内容溢出但不出现滚动条 */
                justify-content: center; /* 居中显示 */
                flex-wrap: nowrap; /* 强制不换行 */
            }
            .slide-item {
                /* 计算宽度以适应4张：假设容器1140，减去gap，每张约260-280 */
                width: 260px; 
            }
            .slide-item img {
                width: 260px;
                height: 520px; /* 保持比例 */
            }
            .slider-indicator {
                display: none; /* 桌面端不需要滑动提示 */
            }
        }

        /* --- 关键：移动端适配 (显示2.5张) --- */
        @media (max-width: 768px) {
            .features-grid { grid-template-columns: 1fr; gap: 15px; }
            .feature-card { flex-direction: row; text-align: left; padding: 20px; gap: 20px; }
            .icon-box { width: 55px; height: 55px; font-size: 24px; margin-bottom: 0; }
            .tutorial-grid { grid-template-columns: 1fr; gap: 10px; }
            .tutorial-item { flex-direction: row; text-align: left; padding: 20px; gap: 20px; background: #fafafa; }
            .step-blob { width: 45px; height: 45px; font-size: 18px; margin-bottom: 0; }
            
            .download-zone h2 { font-size: 2rem; }
            .btn-group { gap: 15px; }
            .download-btn-white { padding: 14px 30px; font-size: 14px; }

            /* 移动端滑块核心设置 */
            .app-slider-container {
                padding: 0 10px 60px 10px; /* 减少左右padding，让内容更贴近边缘 */
            }
            .app-slider {
                gap: 12px; /* 较小的间距 */
                padding-left: 15px;  /* 左侧留白，让第一张图不完全贴边 */
                padding-right: 15px;
                overflow-x: auto; /* 必须保留滑动 */
                justify-content: flex-start;
            }

            .slide-item {
                /* 核心算法：显示2.5张 */
                /* 屏幕宽度假设 360px - 30px(padding) = 330px */
                /* 330 / 2.5 = 132px */
                /* 设置 width 为 38vw 左右，配合 gap 12px，刚好能看到2张半 */
                width: 38vw; 
                max-width: 140px; /* 限制最大宽度，防止平板上太大 */
            }

            .slide-item img {
                width: 100%;
                height: auto;
                aspect-ratio: 300 / 600; /* 强制保持 1:2 比例 */
            }

            .slide-caption {
                font-size: 11px; /* 字体相应缩小 */
                margin-top: 8px;
                padding-bottom: 2px;
            }
            
            .slider-indicator {
                font-size: 11px;
                margin-top: -20px;
            }
        }
        
        /* 中等屏幕适配 (平板等) */
        @media (min-width: 769px) and (max-width: 1299px) {
             .app-slider {
                justify-content: center;
                overflow-x: auto; /* 如果屏幕不够宽放4张，则允许滑动 */
            }
            .slide-item {
                width: 240px;
            }
            .slide-item img {
                width: 240px;
                height: 480px;
            }
        }

        .reveal { opacity: 0; transform: translateY(30px); transition: 0.8s ease-out; }
        .reveal.active { opacity: 1; transform: translateY(0); }