:root{
    --blue:#2f7feb;
    --blue-dark:#1f63c4;
    --blue-soft:#eaf2fe;
    --ink:#101418;
    --ink-2:#333a44;
    --gray:#6b7480;
    --line:#e6eaf0;
    --bg:#ffffff;
    --bg-soft:#f6f8fb;
    --radius:14px;
    --shadow:0 6px 24px rgba(23,43,77,.07);
  }
  *{box-sizing:border-box;margin:0;padding:0;}
  html{scroll-behavior:smooth;}
  body{
    font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
    color:var(--ink);
    background:var(--bg);
    line-height:1.7;
    -webkit-font-smoothing:antialiased;
    overflow-x:hidden;
  }
  img{max-width:100%;display:block;}
  a{color:inherit;text-decoration:none;}
  ul,ol{list-style:none;}
  .wrap{width:100%;max-width:1140px;margin:0 auto;padding:0 20px;}
  .btn{
    display:inline-flex;align-items:center;justify-content:center;gap:8px;
    padding:13px 26px;border-radius:10px;font-size:15px;font-weight:600;
    border:1px solid transparent;cursor:pointer;transition:transform .18s ease,box-shadow .18s ease,background .18s ease;
  }
  .btn-primary{background:var(--blue);color:#fff;box-shadow:0 6px 16px rgba(47,127,235,.28);}
  .btn-primary:hover{background:var(--blue-dark);transform:translateY(-2px);}
  .btn-ghost{background:#fff;color:var(--ink);border-color:var(--line);}
  .btn-ghost:hover{border-color:var(--blue);color:var(--blue);}

  /* ---------- header ---------- */
  .site-header{
    position:sticky;top:0;z-index:50;background:rgba(255,255,255,.92);
    backdrop-filter:blur(8px);border-bottom:1px solid var(--line);
  }
  .header-inner{display:flex;align-items:center;justify-content:space-between;height:64px;gap:16px;}
  .brand{display:flex;align-items:center;gap:10px;font-size:18px;font-weight:800;letter-spacing:.5px;white-space:nowrap;}
  .brand img{height:32px;width:auto;border-radius:8px;}
  .nav{display:flex;align-items:center;gap:22px;font-size:14px;color:var(--ink-2);}
  .nav a{position:relative;padding:4px 0;white-space:nowrap;}
  .nav a::after{content:"";position:absolute;left:0;bottom:-2px;width:0;height:2px;background:var(--blue);transition:width .2s ease;}
  .nav a:hover{color:var(--blue);}
  .nav a:hover::after{width:100%;}
  .header-cta{display:flex;align-items:center;gap:10px;}
  .header-cta .btn{padding:9px 18px;font-size:14px;}
  .nav-toggle{display:none;background:none;border:1px solid var(--line);border-radius:8px;width:40px;height:36px;flex-direction:column;justify-content:center;align-items:center;gap:4px;cursor:pointer;}
  .nav-toggle span{display:block;width:18px;height:2px;background:var(--ink);border-radius:2px;}

  /* ---------- hero ---------- */
  .hero{
    position:relative;
    background:
      linear-gradient(rgba(47,127,235,.055) 1px,transparent 1px) 0 0/48px 48px,
      linear-gradient(90deg,rgba(47,127,235,.055) 1px,transparent 1px) 0 0/48px 48px,
      linear-gradient(180deg,#f8fbff 0%,#ffffff 100%);
    padding:76px 0 84px;overflow:hidden;
  }
  .hero::after{content:"";position:absolute;right:-160px;top:-120px;width:520px;height:520px;border-radius:50%;background:radial-gradient(circle,rgba(47,127,235,.12),transparent 68%);pointer-events:none;}
  .hero-inner{display:grid;grid-template-columns:1.05fr .95fr;gap:56px;align-items:center;position:relative;z-index:2;}
  .hero-tag{display:inline-flex;align-items:center;gap:8px;background:var(--blue-soft);color:var(--blue-dark);font-size:13px;font-weight:600;padding:6px 14px;border-radius:999px;margin-bottom:20px;}
  .hero-tag i{width:7px;height:7px;border-radius:50%;background:var(--blue);display:inline-block;}
  .hero h1{font-size:46px;line-height:1.22;font-weight:800;letter-spacing:-.5px;}
  .hero h1 em{font-style:normal;color:var(--blue);}
  .hero-desc{margin-top:20px;font-size:16px;color:var(--gray);max-width:480px;}
  .hero-points{display:flex;flex-wrap:wrap;gap:10px;margin-top:24px;}
  .hero-points span{font-size:13px;font-weight:600;color:var(--ink-2);background:#fff;border:1px solid var(--line);border-radius:8px;padding:7px 13px;box-shadow:var(--shadow);}
  .hero-actions{display:flex;flex-wrap:wrap;gap:14px;margin-top:32px;}
  .hero-note{margin-top:16px;font-size:13px;color:var(--gray);}

  /* phone carousel */
  .hero-visual{position:relative;display:flex;justify-content:center;}
  .phone{
    position:relative;width:270px;background:#fff;border-radius:34px;padding:12px;
    border:1px solid var(--line);box-shadow:0 26px 60px rgba(23,43,77,.16);
  }
  .phone-notch{position:absolute;top:12px;left:50%;transform:translateX(-50%);width:88px;height:18px;background:#101418;border-radius:0 0 12px 12px;z-index:3;}
  .phone-screen{position:relative;border-radius:24px;overflow:hidden;aspect-ratio:9/17;background:#eef2f8;}
  .phone-slide{position:absolute;inset:0;opacity:0;transition:opacity .8s ease;}
  .phone-slide.active{opacity:1;}
  .phone-slide img{width:100%;height:100%;object-fit:cover;object-position:top center;}
  .phone-caption{position:absolute;left:12px;right:12px;bottom:12px;background:rgba(16,20,24,.62);color:#fff;font-size:12px;padding:7px 12px;border-radius:8px;backdrop-filter:blur(4px);}
  .dots{display:flex;justify-content:center;gap:7px;margin-top:16px;}
  .dots button{width:7px;height:7px;border-radius:50%;border:0;background:#c9d6e8;cursor:pointer;padding:0;transition:all .25s;}
  .dots button.on{width:20px;border-radius:4px;background:var(--blue);}
  .float-card{
    position:absolute;background:#fff;border:1px solid var(--line);border-radius:12px;box-shadow:var(--shadow);
    padding:10px 14px;font-size:12px;font-weight:600;color:var(--ink-2);display:flex;align-items:center;gap:8px;
  }
  .float-card b{color:var(--blue);}
  .fc-1{left:-6px;top:66px;animation:bob 5s ease-in-out infinite;}
  .fc-2{right:-14px;bottom:96px;animation:bob 6s ease-in-out infinite .8s;}
  @keyframes bob{0%,100%{transform:translateY(0);}50%{transform:translateY(-9px);}}

  /* ---------- section common ---------- */
  .section{padding:78px 0;}
  .section.soft{background:var(--bg-soft);}
  .sec-head{max-width:680px;margin-bottom:42px;}
  .sec-head.center{margin-left:auto;margin-right:auto;text-align:center;}
  .sec-kicker{display:inline-block;font-size:13px;font-weight:700;color:var(--blue);letter-spacing:1px;margin-bottom:10px;}
  .sec-head h2{font-size:31px;line-height:1.3;font-weight:800;letter-spacing:-.3px;}
  .sec-head p{margin-top:14px;color:var(--gray);font-size:15px;}

  /* features: 瀑布流/网格卡片 */
  .feat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;}
  .feat-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px 20px;box-shadow:var(--shadow);transition:transform .2s ease,border-color .2s ease;}
  .feat-card:hover{transform:translateY(-4px);border-color:#cfe0fa;}
  .feat-ico{width:42px;height:42px;border-radius:11px;background:var(--blue-soft);color:var(--blue-dark);display:flex;align-items:center;justify-content:center;font-size:18px;font-weight:800;margin-bottom:14px;}
  .feat-card h3{font-size:16px;font-weight:700;margin-bottom:8px;}
  .feat-card p{font-size:13.5px;color:var(--gray);}

  /* Z 字型 */
  .z-row{display:grid;grid-template-columns:1fr 1fr;gap:56px;align-items:center;margin-bottom:64px;}
  .z-row:last-child{margin-bottom:0;}
  .z-row.rev .z-media{order:2;}
  .z-media{border-radius:18px;overflow:hidden;border:1px solid var(--line);box-shadow:var(--shadow);background:#fff;}
  .z-media img{width:100%;height:100%;object-fit:cover;}
  .z-text h3{font-size:23px;font-weight:800;margin-bottom:14px;}
  .z-text p{color:var(--gray);font-size:15px;margin-bottom:18px;}
  .z-list li{display:flex;gap:12px;padding:9px 0;font-size:14px;color:var(--ink-2);}
  .z-list li::before{content:"✓";color:var(--blue);font-weight:800;}

  /* 标签 */
  .tag-wall{display:flex;flex-wrap:wrap;gap:12px;}
  .tag-wall a{font-size:14px;font-weight:600;padding:11px 20px;border-radius:999px;background:#fff;border:1px solid var(--line);color:var(--ink-2);transition:all .2s;}
  .tag-wall a:hover{background:var(--blue);border-color:var(--blue);color:#fff;transform:translateY(-2px);}
  .tag-wall a.hot{background:var(--blue-soft);color:var(--blue-dark);border-color:#d3e4fd;}

  /* 榜单阶梯 */
  .rank-wrap{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;align-items:end;}
  .rank-card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;box-shadow:var(--shadow);display:flex;flex-direction:column;}
  .rank-card .rc-cover{position:relative;aspect-ratio:3/4;overflow:hidden;background:#eef2f8;}
  .rank-card .rc-cover img{width:100%;height:100%;object-fit:cover;transition:transform .4s ease;}
  .rank-card:hover .rc-cover img{transform:scale(1.05);}
  .rank-num{position:absolute;top:10px;left:10px;background:#101418;color:#fff;font-size:12px;font-weight:700;padding:4px 10px;border-radius:6px;}
  .rc-body{padding:16px 16px 20px;}
  .rc-body b{display:block;font-size:15px;margin-bottom:6px;}
  .rc-body span{font-size:12.5px;color:var(--gray);}
  .rank-card.top1{transform:translateY(-18px);border-color:#cfe0fa;}
  .rank-card.top1 .rank-num{background:var(--blue);}

  /* 应用截图 */
  .shots-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:16px;align-items:start;}
  .shot{border-radius:16px;overflow:hidden;border:1px solid var(--line);box-shadow:var(--shadow);background:#fff;transition:transform .22s ease;}
  .shot:hover{transform:translateY(-5px);}
  .shot img{width:100%;height:auto;}
  .shot:nth-child(even){margin-top:26px;}

  /* 评论 */
  .review-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px;}
  .review{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:22px;box-shadow:var(--shadow);display:flex;gap:14px;}
  .review-avatar{width:46px;height:46px;border-radius:12px;overflow:hidden;flex:0 0 46px;border:1px solid var(--line);}
  .review-avatar img{width:100%;height:100%;object-fit:cover;}
  .review-body b{font-size:14px;display:block;margin-bottom:2px;}
  .review-meta{font-size:12px;color:#9aa4b2;margin-bottom:8px;}
  .review-body p{font-size:13.5px;color:var(--ink-2);}
  .review-stars{color:var(--blue);font-size:12px;letter-spacing:2px;margin-top:8px;}

  /* 安全 */
  .safe-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:52px;align-items:center;}
  .safe-list{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin-top:26px;}
  .safe-item{background:#fff;border:1px solid var(--line);border-radius:12px;padding:18px;box-shadow:var(--shadow);}
  .safe-item b{display:block;font-size:14.5px;margin-bottom:6px;}
  .safe-item span{font-size:13px;color:var(--gray);}
  .safe-img{border-radius:18px;overflow:hidden;border:1px solid var(--line);box-shadow:var(--shadow);}
  .safe-img img{width:100%;height:100%;object-fit:cover;}

  /* FAQ */
  .faq-list{max-width:820px;margin:0 auto;border-top:1px solid var(--line);}
  .faq-item{border-bottom:1px solid var(--line);}
  .faq-q{width:100%;background:none;border:0;text-align:left;display:flex;align-items:center;justify-content:space-between;gap:16px;padding:22px 4px;font-size:15.5px;font-weight:700;color:var(--ink);cursor:pointer;font-family:inherit;}
  .faq-q i{font-style:normal;color:var(--blue);font-size:20px;font-weight:400;transition:transform .2s;}
  .faq-item.open .faq-q i{transform:rotate(45deg);}
  .faq-a{max-height:0;overflow:hidden;transition:max-height .3s ease;color:var(--gray);font-size:14px;}
  .faq-a p{padding:0 4px 22px;}
  .faq-item.open .faq-a{max-height:260px;}

  /* download */
  .download{background:linear-gradient(180deg,#f2f7ff 0%,#ffffff 100%);}
  .download-panel{background:#fff;border:1px solid var(--line);border-radius:22px;box-shadow:0 18px 50px rgba(23,43,77,.09);padding:46px;display:grid;grid-template-columns:1.15fr .85fr;gap:48px;align-items:center;}
  .download-panel h2{font-size:30px;font-weight:800;line-height:1.3;}
  .download-panel > div > p{color:var(--gray);margin-top:14px;font-size:15px;}
  .steps{margin-top:28px;display:grid;gap:14px;}
  .step{display:flex;gap:14px;align-items:flex-start;}
  .step-no{flex:0 0 30px;height:30px;border-radius:9px;background:var(--blue-soft);color:var(--blue-dark);font-weight:800;font-size:13px;display:flex;align-items:center;justify-content:center;}
  .step-txt b{display:block;font-size:14.5px;margin-bottom:2px;}
  .step-txt span{font-size:13px;color:var(--gray);}
  .dl-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:28px;}
  .qr-box{text-align:center;border:1px dashed #cfe0fa;border-radius:18px;padding:22px;background:#fbfdff;}
  .qr-box img{width:170px;height:170px;margin:0 auto 12px;border-radius:10px;background:#fff;padding:6px;border:1px solid var(--line);}
  .qr-box b{font-size:14px;display:block;}
  .qr-box span{font-size:12.5px;color:var(--gray);}
  .dl-url{margin-top:14px;font-size:12px;color:#8b95a3;word-break:break-all;}

  /* footer */
  .site-footer{background:#0f1520;color:#b7c0cd;padding:52px 0 26px;}
  .footer-top{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:36px;padding-bottom:34px;border-bottom:1px solid #222c3b;}
  .footer-brand{display:flex;align-items:center;gap:10px;color:#fff;font-size:17px;font-weight:800;margin-bottom:14px;}
  .footer-brand img{height:30px;width:auto;border-radius:8px;}
  .footer-top p{font-size:13px;line-height:1.9;color:#8e99a8;}
  .footer-col h4{font-size:14px;color:#fff;margin-bottom:14px;font-weight:700;}
  .footer-col a,.footer-col span{display:block;font-size:13px;color:#8e99a8;margin-bottom:9px;}
  .footer-col a:hover{color:#fff;}
  .footer-bottom{display:flex;flex-wrap:wrap;justify-content:space-between;gap:10px;padding-top:22px;font-size:12.5px;color:#6f7a89;}
  .footer-bottom time{color:#6f7a89;}

  /* Baidu modal */
  .bd-mask{position:fixed;inset:0;background:rgba(16,20,24,.55);display:none;align-items:center;justify-content:center;padding:24px;z-index:200;}
  .bd-mask.show{display:flex;}
  .bd-box{background:#fff;border-radius:16px;max-width:420px;width:100%;padding:26px;box-shadow:0 24px 60px rgba(0,0,0,.25);}
  .bd-box h3{font-size:17px;line-height:1.6;margin-bottom:16px;font-weight:700;}
  .bd-link{background:var(--bg-soft);border:1px solid var(--line);border-radius:10px;padding:12px;font-size:13px;word-break:break-all;color:var(--ink-2);margin-bottom:16px;}
  .bd-box .btn{width:100%;}
  .bd-close{margin-top:12px;display:block;width:100%;background:none;border:0;color:#8b95a3;font-size:13px;cursor:pointer;font-family:inherit;padding:8px;}

  @media (max-width:1024px){
    .hero h1{font-size:38px;}
    .hero-inner{gap:36px;}
    .feat-grid{grid-template-columns:repeat(2,1fr);}
    .shots-grid{grid-template-columns:repeat(4,1fr);}
    .footer-top{grid-template-columns:1fr 1fr;gap:28px;}
    .download-panel{padding:34px;gap:32px;}
  }
  @media (max-width:768px){
    .nav{
      display:none;position:absolute;top:64px;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);
      flex-direction:column;align-items:flex-start;gap:0;padding:8px 20px 16px;box-shadow:0 14px 24px rgba(23,43,77,.08);
    }
    .nav.open{display:flex;}
    .nav a{width:100%;padding:12px 0;border-bottom:1px solid var(--line);font-size:15px;}
    .nav a:last-child{border-bottom:0;}
    .nav-toggle{display:flex;}
    .header-cta .btn{padding:8px 14px;font-size:13px;}
    .hero{padding:48px 0 56px;}
    .hero-inner{grid-template-columns:1fr;gap:44px;}
    .hero h1{font-size:31px;}
    .hero-desc{font-size:15px;}
    .section{padding:56px 0;}
    .sec-head h2{font-size:25px;}
    .feat-grid{grid-template-columns:1fr;}
    .z-row{grid-template-columns:1fr;gap:24px;margin-bottom:44px;}
    .z-row.rev .z-media{order:0;}
    .rank-wrap{grid-template-columns:1fr;align-items:stretch;gap:16px;}
    .rank-card.top1{transform:none;}
    .rank-card .rc-cover{aspect-ratio:16/10;}
    .shots-grid{grid-template-columns:repeat(2,1fr);gap:12px;}
    .shot:nth-child(even){margin-top:0;}
    .review-grid{grid-template-columns:1fr;}
    .safe-grid{grid-template-columns:1fr;gap:30px;}
    .safe-list{grid-template-columns:1fr;}
    .download-panel{grid-template-columns:1fr;padding:26px 20px;gap:30px;}
    .download-panel h2{font-size:24px;}
    .qr-box img{width:150px;height:150px;}
    .footer-top{grid-template-columns:1fr;gap:26px;}
    .phone{width:236px;}
    .float-card{display:none;}
    .dl-actions .btn{flex:1 1 100%;}
  }