:root {
      --ink: #142033;
      --muted: #617087;
      --line: #dfe7ef;
      --paper: #f7fafc;
      --white: #ffffff;
      --navy: #09121f;
      --cyan: #16d9c2;
      --blue: #4d79ff;
      --pink: #fa4ca4;
      --yellow: #ffd166;
      --shadow: 0 18px 45px rgba(17, 39, 67, .10);
      --radius: 14px;
      --container: 1180px;
    }
    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      color: var(--ink);
      background: var(--paper);
      font-family: Inter, "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
      line-height: 1.7;
      overflow-x: hidden;
    }
    a { color: inherit; text-decoration: none; }
    img { max-width: 100%; height: auto; display: block; }
    .container { width: min(var(--container), calc(100% - 40px)); margin: 0 auto; }
    .site-header {
      position: sticky;
      top: 0;
      z-index: 20;
      background: rgba(9, 18, 31, .96);
      border-bottom: 1px solid rgba(255,255,255,.10);
      backdrop-filter: blur(12px);
    }
    .nav {
      min-height: 76px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 24px;
    }
    .brand {
      display: inline-flex;
      align-items: center;
      flex-shrink: 0;
      color: #fff;
    }
    .ai-page-logo { width: 142px; height: auto; }
    .nav-links {
      display: flex;
      align-items: center;
      justify-content: flex-end;
      gap: 0;
      flex-wrap: wrap;
    }
    .nav-links a {
      color: #dbe8f5;
      font-size: 13px;
      padding: 8px 9px;
      transition: color .2s ease;
    }
    .nav-links a:hover { color: var(--cyan); }
    .nav-cta, .button {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      border: 0;
      border-radius: 8px;
      padding: 12px 20px;
      font-weight: 700;
      cursor: pointer;
      transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
    }
    .nav-cta {
      color: var(--navy);
      background: var(--cyan);
      white-space: nowrap;
      font-size: 13px;
    }
    .button:hover, .nav-cta:hover { transform: translateY(-2px); box-shadow: 0 10px 25px rgba(22,217,194,.24); }
    .button-primary { color: var(--navy); background: var(--cyan); }
    .button-dark { color: #fff; background: var(--navy); }
    .button-ghost { color: var(--ink); background: #fff; border: 1px solid var(--line); }
    .menu-toggle { display: none; color: #fff; background: transparent; border: 1px solid rgba(255,255,255,.3); border-radius: 7px; padding: 8px 11px; font-size: 18px; }
    .hero {
      position: relative;
      overflow: hidden;
      color: #fff;
      background:
        linear-gradient(120deg, rgba(9,18,31,1) 0%, rgba(11,29,47,1) 56%, rgba(18,39,64,1) 100%);
      padding: 88px 0 74px;
    }
    .hero:before, .hero:after {
      content: "";
      position: absolute;
      border: 1px solid rgba(22,217,194,.28);
      transform: rotate(22deg);
      pointer-events: none;
    }
    .hero:before { width: 380px; height: 380px; right: -100px; top: -110px; border-radius: 30px; }
    .hero:after { width: 230px; height: 230px; left: -100px; bottom: -120px; border-radius: 50%; border-color: rgba(250,76,164,.3); }
    .hero-grid { display: grid; grid-template-columns: 1.05fr .95fr; gap: 62px; align-items: center; position: relative; z-index: 1; }
    .eyebrow, .section-kicker {
      color: var(--cyan);
      font-size: 12px;
      font-weight: 800;
      letter-spacing: 2px;
      text-transform: uppercase;
    }
    .hero h1 { max-width: 680px; margin: 14px 0 20px; font-size: clamp(38px, 5vw, 68px); line-height: 1.12; letter-spacing: 0; }
    .hero h1 em { color: var(--cyan); font-style: normal; }
    .hero-copy { max-width: 650px; color: #c7d6e7; font-size: 18px; }
    .hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
    .hero .button-ghost { color: #fff; background: transparent; border-color: rgba(255,255,255,.35); }
    .hero-panel { border-left: 1px solid rgba(255,255,255,.20); padding-left: 34px; }
    .hero-panel h2 { margin: 0 0 18px; font-size: 20px; }
    .hero-panel p { color: #b8c9da; margin: 0 0 22px; }
    .signal-list { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
    .signal { padding: 17px; border: 1px solid rgba(255,255,255,.14); background: rgba(255,255,255,.06); border-radius: 9px; }
    .signal strong { display: block; color: var(--yellow); font-size: 26px; line-height: 1.2; }
    .signal span { color: #c8d8e6; font-size: 13px; }
    section { padding: 82px 0; }
    .section-head { display: flex; align-items: end; justify-content: space-between; gap: 24px; margin-bottom: 34px; }
    .section-head h2 { margin: 7px 0 0; font-size: clamp(28px, 4vw, 43px); line-height: 1.2; }
    .section-head p { max-width: 530px; margin: 0; color: var(--muted); }
    .intro { background: #fff; }
    .intro-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 44px; align-items: start; }
    .intro h2 { margin: 10px 0 16px; font-size: 38px; line-height: 1.25; }
    .intro p { color: var(--muted); }
    .metric-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .metric { padding: 22px; border-top: 3px solid var(--cyan); background: var(--paper); }
    .metric:nth-child(2) { border-color: var(--pink); }
    .metric:nth-child(3) { border-color: var(--blue); }
    .metric:nth-child(4) { border-color: var(--yellow); }
    .metric strong { display: block; font-size: 29px; color: var(--navy); }
    .metric span { color: var(--muted); font-size: 14px; }
    .service-section { background: linear-gradient(135deg, #eef8f8 0%, #f8f7fc 100%); }
    .service-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
    .service-card, .review, .case-card, .article-card, .help-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); box-shadow: 0 7px 22px rgba(24,47,73,.04); }
    .service-card { padding: 23px; transition: transform .25s ease, box-shadow .25s ease; }
    .service-card:hover, .review:hover, .case-card:hover, .article-card:hover { transform: translateY(-5px); box-shadow: var(--shadow); }
    .service-icon { width: 42px; height: 42px; display: grid; place-items: center; margin-bottom: 16px; border-radius: 10px; color: var(--navy); background: var(--cyan); font-weight: 900; }
    .service-card:nth-child(2n) .service-icon { background: var(--pink); }
    .service-card:nth-child(3n) .service-icon { background: var(--yellow); }
    .service-card h3 { margin: 0 0 8px; font-size: 18px; }
    .service-card p { margin: 0; color: var(--muted); font-size: 14px; }
    .workflow { background: var(--navy); color: #fff; }
    .workflow .section-head p { color: #b8c8d9; }
    .step-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 0; }
    .step { position: relative; padding: 22px 18px 10px 0; }
    .step:not(:last-child):after { content: ""; position: absolute; top: 37px; right: 18px; width: calc(100% - 65px); height: 1px; background: rgba(22,217,194,.42); }
    .step-number { position: relative; z-index: 1; width: 48px; height: 48px; display: grid; place-items: center; margin-bottom: 22px; border-radius: 50%; color: var(--navy); background: var(--cyan); font-weight: 900; }
    .step h3 { font-size: 17px; margin: 0 0 8px; }
    .step p { color: #b8c8d9; font-size: 14px; margin: 0; padding-right: 16px; }
    .solutions { background: #fff; }
    .solution-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
    .solution { padding: 24px; border: 1px solid var(--line); background: linear-gradient(145deg, #fff, #f5f9fc); }
    .solution h3 { margin: 0 0 9px; }
    .solution p { margin: 0; color: var(--muted); font-size: 14px; }
    .tag-cloud { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 28px; }
    .tag { padding: 7px 12px; border-radius: 100px; border: 1px solid #cdd9e7; color: #43566d; background: #f8fbfd; font-size: 13px; }
    .network { background: #f0f7f8; }
    .network-grid { display: grid; grid-template-columns: .9fr 1.1fr; gap: 42px; align-items: center; }
    .network-copy h2 { font-size: 36px; margin: 9px 0 15px; }
    .network-copy p { color: var(--muted); }
    .model-wall { display: flex; flex-wrap: wrap; gap: 10px; }
    .model { padding: 11px 14px; color: #173244; background: #fff; border-left: 3px solid var(--pink); box-shadow: 0 5px 15px rgba(30,56,79,.07); }
    .model:nth-child(3n) { border-color: var(--cyan); }
    .model:nth-child(4n) { border-color: var(--yellow); }
    .comparison { background: #fff; }
    .score-line { display: flex; align-items: center; gap: 22px; margin-bottom: 25px; }
    .score { color: var(--pink); font-size: 40px; font-weight: 900; line-height: 1; }
    .stars { color: #f3ac1d; letter-spacing: 3px; font-size: 22px; }
    .table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: 10px; }
    table { width: 100%; min-width: 720px; border-collapse: collapse; background: #fff; }
    th, td { padding: 16px 18px; border-bottom: 1px solid var(--line); text-align: left; font-size: 14px; }
    th { color: #fff; background: var(--navy); }
    td:first-child { font-weight: 700; }
    tr:last-child td { border-bottom: 0; }
    .good { color: #068f83; font-weight: 800; }
    .cases { background: linear-gradient(135deg, #f9fbfd, #eef8f7); }
    .case-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
    .case-card { overflow: hidden; }
    .case-card img { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
    .case-content { padding: 20px; }
    .case-content h3 { margin: 0 0 7px; }
    .case-content p { margin: 0; color: var(--muted); font-size: 14px; }
    .reviews { background: #fff; }
    .review-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
    .review { padding: 23px; transition: transform .25s ease, box-shadow .25s ease; }
    .review-top { display: flex; justify-content: space-between; gap: 12px; margin-bottom: 14px; }
    .review strong { display: block; }
    .review small { color: var(--muted); }
    .review-rating { color: #e9a61a; white-space: nowrap; }
    .review p { margin: 0; color: #45586d; font-size: 14px; }
    .pricing { background: var(--navy); color: #fff; }
    .pricing .section-head p { color: #b8c8d9; }
    .price-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 15px; }
    .price-card { padding: 24px; border: 1px solid rgba(255,255,255,.16); background: rgba(255,255,255,.06); }
    .price-card.featured { border-color: var(--cyan); background: rgba(22,217,194,.09); }
    .price-card h3 { margin: 0 0 12px; }
    .price-card p { margin: 0 0 14px; color: #bdcedd; font-size: 14px; }
    .price-card strong { color: var(--yellow); font-size: 24px; }
    .help { background: #f5f8fa; }
    .help-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
    .help-card { padding: 23px; }
    .help-card h3 { margin: 0 0 9px; }
    .help-card p { margin: 0; color: var(--muted); font-size: 14px; }
    .faq { background: #fff; }
    .faq-list { max-width: 880px; margin: 0 auto; }
    details { border-bottom: 1px solid var(--line); }
    summary { display: flex; justify-content: space-between; gap: 20px; padding: 19px 0; cursor: pointer; font-weight: 800; list-style: none; }
    summary::-webkit-details-marker { display: none; }
    summary:after { content: "+"; color: var(--pink); font-size: 22px; line-height: 1; }
    details[open] summary:after { content: "−"; }
    details p { margin: -5px 0 18px; color: var(--muted); max-width: 780px; }
    .knowledge { background: linear-gradient(135deg, #eef8f8, #fff5fa); }
    .knowledge-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; }
    .knowledge h2 { margin: 8px 0 14px; font-size: 35px; }
    .knowledge p { color: var(--muted); }
    .timeline { border-left: 2px solid var(--cyan); padding-left: 24px; }
    .timeline-item { position: relative; margin-bottom: 20px; }
    .timeline-item:before { content: ""; position: absolute; width: 10px; height: 10px; left: -31px; top: 9px; border-radius: 50%; background: var(--pink); }
    .timeline-item strong { display: block; }
    .timeline-item span { color: var(--muted); font-size: 14px; }
    .articles { background: #fff; }
    .article-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 13px; }
    .article-card { padding: 18px; min-height: 150px; }
    .article-card small { color: var(--pink); font-weight: 800; }
    .article-card h3 { margin: 10px 0 0; font-size: 16px; line-height: 1.45; }
    .contact { background: #edf7f7; }
    .contact-grid { display: grid; grid-template-columns: .85fr 1.15fr; gap: 40px; align-items: start; }
    .contact h2 { margin: 8px 0 15px; font-size: 37px; }
    .contact-copy p { color: var(--muted); }
    .contact-list { display: grid; gap: 10px; margin-top: 22px; }
    .contact-item { padding: 13px 15px; background: #fff; border-left: 3px solid var(--cyan); }
    .form-box { padding: 26px; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); }
    .form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 15px; }
    .field { display: grid; gap: 6px; }
    .field.full { grid-column: 1 / -1; }
    label { font-size: 13px; font-weight: 800; }
    input, select, textarea { width: 100%; padding: 12px 13px; border: 1px solid #ccd8e3; border-radius: 7px; color: var(--ink); background: #fbfdff; font: inherit; outline: none; }
    input:focus, select:focus, textarea:focus { border-color: var(--cyan); box-shadow: 0 0 0 3px rgba(22,217,194,.13); }
    textarea { min-height: 120px; resize: vertical; }
    .form-submit { margin-top: 17px; width: 100%; }
    .join { background: var(--navy); color: #fff; }
    .join-inner { display: flex; align-items: center; justify-content: space-between; gap: 30px; }
    .join h2 { margin: 0 0 8px; font-size: 32px; }
    .join p { margin: 0; color: #bccddd; }
    .site-footer { color: #c2d0de; background: #07101b; padding: 42px 0 22px; }
    .footer-grid { display: grid; grid-template-columns: 1.2fr .8fr .8fr; gap: 35px; padding-bottom: 30px; }
    .footer-brand p { max-width: 380px; color: #94a8bb; font-size: 14px; }
    .site-footer h3 { color: #fff; margin: 0 0 12px; font-size: 15px; }
    .site-footer a { color: #c2d0de; font-size: 14px; }
    .site-footer a:hover { color: var(--cyan); }
    .footer-links { display: grid; gap: 7px; }
    .copyright { border-top: 1px solid rgba(255,255,255,.12); padding-top: 18px; color: #8294a7; font-size: 13px; }
    .float-tools { position: fixed; right: 18px; bottom: 18px; z-index: 15; display: grid; gap: 8px; }
    .float-tools a { width: 46px; height: 46px; display: grid; place-items: center; border-radius: 50%; color: var(--navy); background: var(--cyan); box-shadow: 0 8px 20px rgba(0,0,0,.15); font-weight: 900; }
    .float-tools a:last-child { background: var(--yellow); }
    .reveal { opacity: 0; transform: translateY(18px); transition: opacity .65s ease, transform .65s ease; }
    .reveal.visible { opacity: 1; transform: translateY(0); }
    @media (max-width: 1040px) {
      .nav-links a { padding-left: 6px; padding-right: 6px; }
      .service-grid { grid-template-columns: repeat(3, 1fr); }
      .article-grid { grid-template-columns: repeat(3, 1fr); }
    }
    @media (max-width: 820px) {
      .container { width: min(var(--container), calc(100% - 28px)); }
      .nav { min-height: 68px; }
      .menu-toggle { display: block; }
      .nav-links { display: none; position: absolute; left: 14px; right: 14px; top: 68px; padding: 12px; background: var(--navy); border: 1px solid rgba(255,255,255,.15); border-radius: 8px; }
      .nav-links.open { display: grid; }
      .nav-links a { padding: 10px 12px; }
      .nav-cta { display: none; }
      .hero { padding: 64px 0 58px; }
      .hero-grid, .intro-grid, .network-grid, .knowledge-grid, .contact-grid { grid-template-columns: 1fr; gap: 32px; }
      .hero-panel { border-left: 0; border-top: 1px solid rgba(255,255,255,.2); padding: 28px 0 0; }
      .service-grid, .review-grid, .case-grid, .help-grid { grid-template-columns: repeat(2, 1fr); }
      .step-grid { grid-template-columns: 1fr; gap: 22px; }
      .step { padding: 0 0 0 70px; }
      .step-number { position: absolute; left: 0; top: 0; }
      .step:not(:last-child):after { left: 23px; right: auto; top: 59px; width: 1px; height: calc(100% + 5px); }
      .price-grid { grid-template-columns: 1fr; }
      .join-inner { align-items: flex-start; flex-direction: column; }
    }
    @media (max-width: 560px) {
      section { padding: 60px 0; }
      .hero h1 { font-size: 39px; }
      .hero-copy { font-size: 16px; }
      .signal-list, .metric-grid, .service-grid, .review-grid, .case-grid, .help-grid, .article-grid, .form-grid { grid-template-columns: 1fr; }
      .section-head { display: block; }
      .section-head p { margin-top: 13px; }
      .footer-grid { grid-template-columns: 1fr; gap: 24px; }
      .form-box { padding: 19px; }
    }