<style>
    /* 全局重置 —— 柔和·蓝色·质感 */
    *{margin:0;padding:0;box-sizing:border-box;font-family:system-ui,'Segoe UI','Helvetica Neue',sans-serif;}
    body{background:#f5f9ff;color:#1a2b3e;line-height:1.5;}
    .container{max-width:1280px;margin:0 auto;padding:0 24px;}
    /* 语义化标签默认样式 */
    header, nav, main, section, article, footer{display:block;}
    a{text-decoration:none;color:inherit;}
    ul{list-style:none;}
    
    /* 柔和蓝色调 */
    :root{
      --primary:#1e6df2;
      --primary-light:#3f8cff;
      --primary-soft:#e3edfe;
      --bg-white:#ffffffdd;
      --glass:rgba(255,255,255,0.75);
      --shadow:0 20px 35px -8px rgba(0,35,90,0.08),0 8px 16px -6px rgba(0,0,0,0.02);
      --border-light:1px solid rgba(30,109,242,0.12);
    }
    .glass-card{
      background:var(--glass); backdrop-filter:blur(2px);
      border-radius:28px; box-shadow:var(--shadow); border:var(--border-light);
      padding:28px 24px; transition: all 0.2s ease;
    }
    .btn{
      display:inline-block; padding:12px 32px; border-radius:60px; font-weight:600;
      background:var(--primary); color:white; box-shadow:0 8px 16px -6px #1e6df280;
      border:none; cursor:pointer; transition:0.15s; text-align:center;
    }
    .btn-outline{
      background:transparent; color:var(--primary); box-shadow:none;
      border:1.5px solid var(--primary);
    }
    .btn:hover{background:#0f54d6; transform:translateY(-2px);}
    .btn-outline:hover{background:var(--primary-soft);}
    
    /* 头部导航 */
    .header-row{
      display:flex; align-items:center; justify-content:space-between; flex-wrap:wrap;
      padding:16px 0; border-bottom:1px solid #c9dfff;
    }
    .logo-area{display:flex; align-items:center; gap:8px;}
    .logo-icon{font-size:32px; color:var(--primary);}
    .logo-text{font-size:24px; font-weight:700; letter-spacing:-0.3px; color:#123a7b;}
    .nav-links{display:flex; gap:32px; font-weight:600; color:#1e3a6b;}
    .nav-links a{padding:8px 0; border-bottom:3px solid transparent;}
    .nav-links a:hover{border-bottom-color:var(--primary);}
    .download-btn-header{background:var(--primary); color:white; padding:10px 22px; border-radius:40px;}
    
    /* footer */
    .footer{background:#e3f0fe; margin-top:60px; padding:48px 0 24px; border-radius:48px 48px 0 0;}
    .footer-grid{display:grid; grid-template-columns:2fr 1fr 1fr 1.5fr; gap:32px;}
    .footer-desc{font-size:0.95rem; color:#1e3a5f;}
    .footer-links h4{font-weight:700; margin-bottom:16px; color:#0f2b4f;}
    .footer-links li{margin-bottom:10px; opacity:0.85;}
    .sub-footer{text-align:center; padding-top:32px; color:#35638f;}
    
    /* 响应式 */
    @media (max-width:768px){
      .header-row{flex-direction:column; gap:12px;}
      .nav-links{flex-wrap:wrap; justify-content:center; gap:20px;}
      .footer-grid{grid-template-columns:1fr; gap:28px;}
      .container{padding:0 18px;}
    }
    
    /* 轮播简易 */
    .carousel-container{position:relative; overflow:hidden; margin:24px 0;}
    .carousel-track{display:flex; transition:transform 0.3s ease; gap:20px;}
    .carousel-card{flex:0 0 calc(33.33% - 14px); min-width:260px; background:white; border-radius:24px; padding:24px; box-shadow:var(--shadow);}
    .carousel-btn{position:absolute; top:50%; transform:translateY(-50%); background:white; border:none; width:46px; height:46px; border-radius:46px; box-shadow:0 6px 12px rgba(0,0,0,0.04); cursor:pointer; z-index:5;}
    .carousel-btn.left{left:-10px;} .carousel-btn.right{right:-10px;}
    @media (max-width:900px){.carousel-card{flex:0 0 calc(50% - 10px);}}
    @media (max-width:600px){.carousel-card{flex:0 0 85%;}}
    
    /* FAQ折叠 */
    details{padding:16px 0; border-bottom:1px solid #cfe2ff;}
    details summary{font-weight:650; cursor:pointer; list-style:none; display:flex; align-items:center;}
    details summary::-webkit-details-marker{display:none;}
    details summary i{transition:0.2s; margin-right:12px; color:var(--primary);}
    details[open] summary i{transform:rotate(90deg);}
    .faq-answer{padding:12px 0 8px 32px; color:#2a405c;}
    
    /* 关键词密度自然布局 */
    .keyword-badge{color:var(--primary); font-weight:500;}
    .rating-stars{color:#f9b81b;}
    
    /* 教程步骤 */
    .step-list{counter-reset:step; margin:20px 0;}
    .step-item{counter-increment:step; margin-bottom:20px; display:flex; gap:16px; align-items:flex-start;}
    .step-item::before{content:counter(step); background:var(--primary); color:white; width:32px; height:32px; border-radius:32px; display:inline-flex; align-items:center; justify-content:center; font-weight:bold; flex-shrink:0;}
    
    /* 下载卡片大气 */
    .hero-download{text-align:center; padding:40px 20px; background:linear-gradient(145deg, #d9eaff, #ffffff); border-radius:56px; margin:40px 0;}
    .big-num{font-size:42px; font-weight:800; color:#10355e;}
  </style>