:root{
      --bg:#f7f9fc;
      --surface:#ffffff;
      --surface-2:#f2f7ff;
      --line:#d9e3f0;
      --text:#132033;
      --muted:#5c6b80;
      --brand:#1f7cff;
      --brand-2:#19c37d;
      --warm:#ffb84d;
      --shadow:0 18px 40px rgba(17,39,78,.08);
      --shadow-soft:0 10px 24px rgba(17,39,78,.06);
      --radius:20px;
      --radius-sm:14px;
      --container:1180px;
    }
    *{box-sizing:border-box}
    html{scroll-behavior:smooth}
    body{
      margin:0;
      font-family: -apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",Arial,sans-serif;
      color:var(--text);
      background:
        radial-gradient(circle at top left, rgba(31,124,255,.10), transparent 26%),
        radial-gradient(circle at top right, rgba(25,195,125,.10), transparent 22%),
        linear-gradient(180deg, #ffffff 0%, #f8fbff 30%, #f5f8fd 100%);
      line-height:1.65;
      overflow-x:hidden;
    }
    a{color:var(--brand); text-decoration:none}
    img{display:block; max-width:100%}
    .container{max-width:var(--container); margin:0 auto; padding:0 20px}
    .topbar{
      position:sticky; top:0; z-index:50;
      backdrop-filter:saturate(180%) blur(14px);
      background:rgba(255,255,255,.84);
      border-bottom:1px solid rgba(217,227,240,.8);
    }
    header .nav{
      display:flex; align-items:center; justify-content:space-between; gap:16px;
      padding:12px 0;
    }
    .brand{
      display:flex; align-items:center; gap:12px; min-width:0;
    }
    .ai-page-logo{width:44px; height:44px; object-fit:contain; border-radius:12px; background:#fff; box-shadow:0 8px 18px rgba(31,124,255,.12)}
    .brand h2{margin:0; font-size:1.02rem; line-height:1.2}
    .brand small{display:block; color:var(--muted); font-size:.84rem; margin-top:2px}
    .menu-btn{
      display:none; border:1px solid var(--line); background:#fff; color:var(--text);
      border-radius:12px; padding:10px 12px; box-shadow:var(--shadow-soft); cursor:pointer;
    }
    nav ul{list-style:none; display:flex; flex-wrap:wrap; align-items:center; gap:14px; padding:0; margin:0}
    nav a{
      color:var(--text); font-weight:600; font-size:.95rem;
      padding:8px 10px; border-radius:10px; transition:.2s ease;
    }
    nav a:hover, nav a:focus{background:#eef5ff; color:var(--brand)}
    .nav-cta{display:flex; gap:10px; align-items:center}
    .btn{
      display:inline-flex; align-items:center; justify-content:center; gap:8px;
      border:1px solid transparent; border-radius:14px; padding:12px 16px;
      font-weight:700; cursor:pointer; transition:.22s ease; white-space:nowrap;
    }
    .btn-primary{background:linear-gradient(135deg, var(--brand), #4d95ff); color:#fff; box-shadow:0 14px 24px rgba(31,124,255,.18)}
    .btn-primary:hover{transform:translateY(-2px); box-shadow:0 18px 30px rgba(31,124,255,.22)}
    .btn-secondary{background:#fff; color:var(--text); border-color:var(--line)}
    .btn-secondary:hover{transform:translateY(-2px); border-color:#b7c8dd}
    .hero{
      position:relative;
      padding:56px 0 28px;
      overflow:hidden;
    }
    .hero::before, .hero::after{
      content:""; position:absolute; border-radius:999px; filter:blur(2px); pointer-events:none;
    }
    .hero::before{width:240px; height:240px; background:rgba(31,124,255,.12); top:20px; right:-70px}
    .hero::after{width:180px; height:180px; background:rgba(25,195,125,.12); left:-60px; bottom:-40px}
    .hero-grid{
      display:grid; grid-template-columns:1.15fr .85fr; gap:28px; align-items:stretch;
    }
    .hero-copy{
      background:linear-gradient(180deg, rgba(255,255,255,.92), rgba(245,249,255,.96));
      border:1px solid rgba(217,227,240,.85); border-radius:28px; padding:30px; box-shadow:var(--shadow);
    }
    .eyebrow{
      display:inline-flex; align-items:center; gap:8px;
      background:#eef6ff; color:#1357c6; border:1px solid #d6e7ff;
      border-radius:999px; padding:7px 12px; font-size:.88rem; font-weight:700;
    }
    h1{margin:16px 0 12px; font-size:clamp(2rem, 4vw, 3.5rem); line-height:1.1; letter-spacing:-.02em}
    .lead{margin:0; font-size:1.05rem; color:var(--muted); max-width:58ch}
    .hero-actions{display:flex; gap:12px; flex-wrap:wrap; margin-top:22px}
    .hero-points{
      display:grid; grid-template-columns:repeat(3,1fr); gap:12px; margin-top:24px;
    }
    .point{
      background:#fff; border:1px solid var(--line); border-radius:18px; padding:14px;
      box-shadow:0 10px 20px rgba(17,39,78,.04);
    }
    .point strong{display:block; font-size:1.08rem}
    .point span{display:block; color:var(--muted); font-size:.92rem; margin-top:4px}
    .hero-side{
      display:grid; gap:14px;
    }
    .hero-card{
      background:linear-gradient(180deg, #ffffff, #f4f9ff);
      border:1px solid rgba(217,227,240,.9); border-radius:24px; padding:20px; box-shadow:var(--shadow-soft);
    }
    .hero-card h3{margin:0 0 10px; font-size:1.05rem}
    .tag-cloud{display:flex; flex-wrap:wrap; gap:10px}
    .tag{
      padding:8px 11px; border-radius:999px; background:#fff; border:1px solid var(--line);
      color:#29415d; font-size:.9rem; font-weight:600;
    }
    .metrics{
      padding:10px 0 28px;
    }
    .section{
      padding:24px 0;
    }
    .section-head{
      display:flex; justify-content:space-between; align-items:end; gap:14px; margin-bottom:16px;
    }
    .section-head h2{margin:0; font-size:1.72rem; line-height:1.15}
    .section-head p{margin:0; color:var(--muted); max-width:60ch}
    .grid-4{display:grid; grid-template-columns:repeat(4,1fr); gap:14px}
    .grid-3{display:grid; grid-template-columns:repeat(3,1fr); gap:14px}
    .grid-2{display:grid; grid-template-columns:repeat(2,1fr); gap:14px}
    .card{
      background:rgba(255,255,255,.92);
      border:1px solid rgba(217,227,240,.9);
      border-radius:var(--radius);
      padding:22px;
      box-shadow:var(--shadow-soft);
      transition:.22s ease;
    }
    .card:hover{transform:translateY(-4px); box-shadow:var(--shadow)}
    .metric .num{font-size:1.85rem; font-weight:800; color:#16386f}
    .metric .label{font-weight:700; margin-top:6px}
    .metric .desc{margin-top:8px; color:var(--muted); font-size:.94rem}
    .feature h3,.case h3,.review h3{margin:0 0 8px; font-size:1.08rem}
    .feature p,.case p,.review p,.article p{margin:0; color:var(--muted)}
    .icon{
      width:44px; height:44px; border-radius:14px; display:grid; place-items:center;
      background:linear-gradient(135deg, rgba(31,124,255,.14), rgba(25,195,125,.12));
      color:#1d61cf; font-weight:800; margin-bottom:12px;
    }
    .split{
      display:grid; grid-template-columns:1fr 1fr; gap:14px; align-items:stretch;
    }
    .panel{
      background:linear-gradient(180deg, #fff, #f7fbff);
      border:1px solid var(--line); border-radius:24px; padding:22px;
    }
    .steps{counter-reset:step}
    .step{
      position:relative; padding:18px 18px 18px 56px;
      background:#fff; border:1px solid var(--line); border-radius:18px;
    }
    .step::before{
      counter-increment:step; content:counter(step);
      position:absolute; left:16px; top:16px; width:28px; height:28px; border-radius:10px;
      background:linear-gradient(135deg, var(--brand), var(--brand-2)); color:#fff;
      display:grid; place-items:center; font-weight:800;
    }
    table{
      width:100%; border-collapse:separate; border-spacing:0; overflow:hidden;
      border:1px solid var(--line); border-radius:20px; background:#fff;
    }
    th,td{padding:14px 12px; text-align:left; border-bottom:1px solid #e7eef7; vertical-align:top}
    th{background:#f5f9ff; font-size:.95rem}
    tr:last-child td{border-bottom:none}
    .score{
      display:flex; align-items:center; gap:12px; flex-wrap:wrap;
      background:linear-gradient(135deg, rgba(31,124,255,.08), rgba(25,195,125,.08));
      border:1px solid rgba(31,124,255,.12); border-radius:20px; padding:18px;
    }
    .stars{color:#f5a623; font-size:1.15rem; letter-spacing:2px}
    details{
      background:#fff; border:1px solid var(--line); border-radius:16px; padding:0 16px; box-shadow:var(--shadow-soft)
    }
    details+details{margin-top:12px}
    summary{
      cursor:pointer; list-style:none; padding:16px 0; font-weight:700; color:var(--text)
    }
    summary::-webkit-details-marker{display:none}
    details p{margin:0 0 16px; color:var(--muted)}
    .articles, .footer-links{display:grid; gap:12px}
    .article{
      padding:18px; background:#fff; border:1px solid var(--line); border-radius:18px;
    }
    .article .meta{font-size:.88rem; color:#6a7a91; margin-bottom:8px}
    .reviews .review{min-height:100%}
    .quote{
      font-size:1.02rem; color:#24364f
    }
    .profile{margin-top:14px; color:var(--muted); font-size:.93rem}
    .form-wrap{
      background:linear-gradient(180deg, #fff, #f4f9ff);
      border:1px solid var(--line); border-radius:28px; padding:24px; box-shadow:var(--shadow);
    }
    form{display:grid; gap:14px}
    .form-grid{display:grid; grid-template-columns:repeat(2,1fr); gap:14px}
    label{display:block; font-weight:700; margin-bottom:7px}
    input, select, textarea{
      width:100%; border:1px solid #d7e2ef; background:#fff; color:var(--text);
      border-radius:14px; padding:13px 14px; font:inherit; outline:none; transition:.2s ease;
    }
    input:focus, select:focus, textarea:focus{border-color:#8bb7ff; box-shadow:0 0 0 4px rgba(31,124,255,.08)}
    textarea{min-height:120px; resize:vertical}
    .help-list{display:grid; gap:10px}
    .help-item{
      display:flex; justify-content:space-between; gap:12px; padding:14px 16px; border:1px solid var(--line);
      border-radius:16px; background:#fff;
    }
    .help-item strong{display:block}
    .help-item span{color:var(--muted); font-size:.92rem}
    .floating{
      position:fixed; right:18px; bottom:18px; z-index:60; display:grid; gap:10px;
    }
    .float-btn{
      display:inline-flex; align-items:center; justify-content:center;
      width:54px; height:54px; border-radius:18px; background:linear-gradient(135deg, var(--brand), #3a87ff);
      color:#fff; box-shadow:0 18px 30px rgba(31,124,255,.22); border:none; cursor:pointer;
    }
    .float-btn.secondary{background:linear-gradient(135deg, #13c27a, #2fd59a)}
    .backtop{opacity:0; visibility:hidden; transform:translateY(8px); transition:.22s ease}
    .backtop.show{opacity:1; visibility:visible; transform:translateY(0)}
    footer{
      margin-top:22px; background:#f2f6fc; border-top:1px solid var(--line); color:var(--text);
    }
    footer a{color:#183b6f}
    .footer-grid{display:grid; grid-template-columns:1.1fr .9fr .9fr; gap:18px; padding:28px 0}
    .footer-bottom{padding:14px 0 24px; color:#52647d; font-size:.92rem; border-top:1px solid #dee7f3}
    .mini{
      display:inline-flex; align-items:center; gap:8px; padding:8px 10px; border-radius:12px;
      background:#fff; border:1px solid var(--line); margin:4px 8px 4px 0;
    }
    .ai-page-image{border-radius:18px; border:1px solid var(--line); box-shadow:var(--shadow-soft)}
    .media-row{display:grid; grid-template-columns:1fr 1fr 1fr; gap:12px}
    .scroll-x{overflow-x:auto; -webkit-overflow-scrolling:touch}
    .table-wrap{overflow-x:auto}
    .nav-panel{
      display:none; padding:0 0 14px;
    }
    .nav-panel.open{display:block}
    .home-link{font-weight:800}
    .muted{color:var(--muted)}
    @media (max-width: 1024px){
      .hero-grid,.grid-4,.grid-3,.split,.footer-grid{grid-template-columns:1fr 1fr}
      .media-row{grid-template-columns:1fr 1fr}
    }
    @media (max-width: 760px){
      .menu-btn{display:inline-flex}
      nav{display:none}
      nav.open{display:block}
      nav ul{flex-direction:column; align-items:flex-start; gap:6px; padding:10px 0 14px}
      .nav{flex-wrap:wrap}
      .nav-cta{width:100%; justify-content:flex-start; flex-wrap:wrap}
      .hero{padding-top:30px}
      .hero-grid,.grid-4,.grid-3,.grid-2,.split,.footer-grid,.form-grid,.media-row,.hero-points{grid-template-columns:1fr}
      .section-head{flex-direction:column; align-items:flex-start}
      .card,.hero-copy,.hero-card,.form-wrap{padding:18px}
      .topbar{position:sticky}
      .floating{right:12px; bottom:12px}
      .btn{width:auto}
      h1{font-size:2rem}
    }
    .fade-in{opacity:0; transform:translateY(18px); transition:.55s ease}
    .fade-in.show{opacity:1; transform:translateY(0)}