:root {
      --ink: #172033;
      --muted: #667085;
      --paper: #fffdf8;
      --white: #ffffff;
      --line: #e6e8ee;
      --blue: #315efb;
      --blue-dark: #2146cf;
      --yellow: #ffd84d;
      --coral: #ff765f;
      --mint: #a9e8d4;
      --lavender: #dcd5ff;
      --peach: #ffe2c6;
      --shadow: 0 18px 50px rgba(29, 43, 80, .10);
      --container: min(1180px, calc(100% - 40px));
    }
    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      color: var(--ink);
      background: var(--paper);
      font-family: "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
      line-height: 1.7;
    }
    a { color: inherit; text-decoration: none; }
    img { max-width: 100%; height: auto; display: block; }
    .container { width: var(--container); margin: 0 auto; }
    .topbar {
      position: sticky;
      top: 0;
      z-index: 20;
      background: rgba(255,253,248,.94);
      border-bottom: 1px solid rgba(230,232,238,.9);
      backdrop-filter: blur(16px);
    }
    .nav {
      min-height: 76px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 22px;
    }
    .brand {
      display: inline-flex;
      align-items: center;
      flex: 0 0 auto;
    }
    .ai-page-logo { width: 142px; }
    .nav-links {
      display: flex;
      align-items: center;
      justify-content: flex-end;
      gap: 0;
      flex-wrap: wrap;
    }
    .nav-links a {
      color: #4e596b;
      font-size: 14px;
      padding: 10px 11px;
      transition: color .2s ease, background .2s ease;
    }
    .nav-links a:hover { color: var(--blue); background: #eef2ff; }
    .nav-cta, .btn {
      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, .btn-primary { color: #fff; background: var(--blue); box-shadow: 0 8px 20px rgba(49,94,251,.22); }
    .nav-cta:hover, .btn-primary:hover { background: var(--blue-dark); transform: translateY(-2px); }
    .menu-toggle { display: none; border: 1px solid var(--line); background: var(--white); border-radius: 7px; padding: 9px 11px; font-size: 20px; }
    .hero {
      position: relative;
      overflow: hidden;
      padding: 86px 0 76px;
      background: #f5f1ff;
      border-bottom: 1px solid #e9e3ff;
    }
    .hero:before, .hero:after {
      content: "";
      position: absolute;
      pointer-events: none;
      border-radius: 45% 55% 60% 40%;
      transform: rotate(-14deg);
    }
    .hero:before {
      width: 330px;
      height: 180px;
      right: -70px;
      top: 35px;
      background: var(--yellow);
      opacity: .7;
    }
    .hero:after {
      width: 240px;
      height: 140px;
      left: -80px;
      bottom: 20px;
      background: var(--mint);
      opacity: .72;
    }
    .hero-grid {
      position: relative;
      z-index: 1;
      display: grid;
      grid-template-columns: minmax(0, 1.1fr) minmax(300px, .9fr);
      gap: 60px;
      align-items: center;
    }
    .eyebrow, .section-kicker {
      display: inline-flex;
      align-items: center;
      color: var(--blue);
      font-size: 13px;
      font-weight: 800;
      letter-spacing: 1px;
      text-transform: uppercase;
    }
    .eyebrow:before, .section-kicker:before {
      content: "";
      width: 28px;
      height: 4px;
      margin-right: 10px;
      background: var(--coral);
      border-radius: 4px;
    }
    h1, h2, h3, p { margin-top: 0; }
    h1 {
      max-width: 700px;
      margin-bottom: 20px;
      font-size: clamp(38px, 6vw, 72px);
      line-height: 1.12;
      letter-spacing: 0;
    }
    .hero-copy {
      max-width: 690px;
      color: #536074;
      font-size: 18px;
    }
    .hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin: 30px 0 28px; }
    .btn-secondary { color: var(--ink); background: var(--white); border: 1px solid #d8ddea; }
    .btn-secondary:hover { transform: translateY(-2px); box-shadow: var(--shadow); }
    .hero-note { color: #667085; font-size: 14px; }
    .hero-panel {
      padding: 25px;
      background: var(--white);
      border: 1px solid #e3e6ef;
      border-radius: 18px;
      box-shadow: var(--shadow);
      transform: rotate(2deg);
    }
    .hero-panel-inner { transform: rotate(-2deg); }
    .hero-panel h2 { margin-bottom: 8px; font-size: 22px; }
    .signal-list { display: grid; gap: 12px; margin: 22px 0 0; padding: 0; list-style: none; }
    .signal-list li {
      display: flex;
      align-items: center;
      gap: 10px;
      padding: 12px 13px;
      border-radius: 8px;
      background: #f8f9fc;
      font-size: 14px;
    }
    .signal-list b { color: var(--blue); font-size: 18px; }
    .section { padding: 88px 0; }
    .section-tint { background: #f4f8f7; }
    .section-lilac { background: #f1efff; }
    .section-head { max-width: 760px; margin-bottom: 38px; }
    h2 { margin-bottom: 14px; font-size: clamp(28px, 4vw, 46px); line-height: 1.2; }
    h3 { margin-bottom: 9px; font-size: 20px; line-height: 1.35; }
    .lead { color: var(--muted); font-size: 17px; }
    .metrics {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 14px;
      margin-top: -1px;
    }
    .metric {
      padding: 26px 20px;
      background: var(--white);
      border-right: 1px solid var(--line);
      border-bottom: 4px solid var(--yellow);
    }
    .metric:nth-child(2) { border-bottom-color: var(--coral); }
    .metric:nth-child(3) { border-bottom-color: var(--mint); }
    .metric:nth-child(4) { border-bottom-color: var(--lavender); }
    .metric strong { display: block; font-size: 32px; line-height: 1; margin-bottom: 8px; }
    .metric span { color: var(--muted); font-size: 14px; }
    .about-grid, .contact-grid, .network-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 46px;
      align-items: start;
    }
    .paint-strip {
      display: grid;
      grid-template-columns: 1.2fr .8fr;
      gap: 12px;
      margin-top: 28px;
    }
    .paint-strip div { min-height: 95px; padding: 16px; border-radius: 12px; font-weight: 800; }
    .paint-strip div:first-child { background: var(--yellow); }
    .paint-strip div:last-child { background: var(--coral); color: #fff; }
    .feature-list { display: grid; gap: 17px; margin: 0; padding: 0; list-style: none; }
    .feature-list li { padding-left: 29px; position: relative; }
    .feature-list li:before {
      content: "✓";
      position: absolute;
      left: 0;
      top: 2px;
      width: 21px;
      height: 21px;
      color: var(--ink);
      background: var(--mint);
      border-radius: 50%;
      text-align: center;
      line-height: 21px;
      font-weight: 800;
    }
    .service-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
    }
    .service-card, .review-card, .article-card, .case-card, .timeline-item {
      background: var(--white);
      border: 1px solid var(--line);
      border-radius: 10px;
      transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
    }
    .service-card:hover, .review-card:hover, .article-card:hover, .case-card:hover, .timeline-item:hover {
      transform: translateY(-5px);
      border-color: #c7d0f7;
      box-shadow: var(--shadow);
    }
    .service-card { padding: 22px; }
    .service-card:nth-child(4n+1) { border-top: 4px solid var(--blue); }
    .service-card:nth-child(4n+2) { border-top: 4px solid var(--coral); }
    .service-card:nth-child(4n+3) { border-top: 4px solid var(--yellow); }
    .service-card:nth-child(4n+4) { border-top: 4px solid #56bfa0; }
    .service-card p, .review-card p, .article-card p, .case-card p { color: var(--muted); font-size: 14px; margin-bottom: 0; }
    .tag-cloud { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 27px; }
    .tag {
      display: inline-flex;
      padding: 7px 12px;
      border-radius: 5px;
      font-size: 13px;
      background: var(--white);
      border: 1px solid #dfe2ea;
    }
    .tag:nth-child(3n+1) { background: #fff3c4; }
    .tag:nth-child(3n+2) { background: #e1f7ef; }
    .tag:nth-child(3n+3) { background: #eeeaff; }
    .process {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 0;
      counter-reset: steps;
    }
    .step {
      position: relative;
      padding: 22px 20px 22px 24px;
      border-top: 3px solid var(--blue);
      background: var(--white);
    }
    .step:not(:last-child):after {
      content: "→";
      position: absolute;
      right: -12px;
      top: 16px;
      z-index: 2;
      width: 24px;
      height: 24px;
      text-align: center;
      line-height: 23px;
      color: var(--blue);
      background: var(--paper);
      font-weight: 900;
    }
    .step-number { color: var(--coral); font-size: 13px; font-weight: 800; }
    .step p { color: var(--muted); font-size: 14px; margin-bottom: 0; }
    .solution-grid, .case-grid, .review-grid, .article-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 18px;
    }
    .solution {
      padding: 26px;
      min-height: 190px;
      border-radius: 16px 5px 16px 5px;
    }
    .solution:nth-child(1) { background: var(--peach); }
    .solution:nth-child(2) { background: var(--mint); }
    .solution:nth-child(3) { background: var(--lavender); }
    .solution p { color: #4f5768; font-size: 14px; }
    .case-card { overflow: hidden; }
    .case-image { aspect-ratio: 16 / 9; overflow: hidden; background: #eef1f7; }
    .case-image img { width: 100%; height: 100%; object-fit: cover; }
    .case-body { padding: 20px; }
    .case-body small { color: var(--blue); font-weight: 800; }
    .compare-wrap { overflow-x: auto; background: var(--white); border: 1px solid var(--line); }
    table { width: 100%; min-width: 760px; border-collapse: collapse; }
    th, td { padding: 16px 18px; text-align: left; border-bottom: 1px solid var(--line); vertical-align: top; }
    th { color: #fff; background: var(--ink); font-size: 14px; }
    td:first-child { font-weight: 700; background: #fafbfe; }
    .rating-box {
      display: flex;
      align-items: center;
      gap: 25px;
      margin-bottom: 25px;
      padding: 20px 24px;
      background: var(--yellow);
      border-radius: 10px;
    }
    .rating-box strong { font-size: 42px; line-height: 1; }
    .stars { color: #d57900; letter-spacing: 3px; font-size: 20px; }
    .timeline { display: grid; gap: 13px; }
    .timeline-item { display: grid; grid-template-columns: 110px 1fr; padding: 18px; }
    .timeline-item time { color: var(--blue); font-weight: 800; }
    .network-list { display: flex; flex-wrap: wrap; gap: 10px; }
    .network-item { padding: 11px 14px; background: var(--white); border: 1px solid var(--line); border-radius: 6px; font-weight: 700; }
    .review-card { padding: 22px; }
    .review-meta { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-bottom: 15px; }
    .review-meta strong { font-size: 15px; }
    .review-meta span { color: var(--blue); font-size: 13px; }
    .faq-list { display: grid; gap: 11px; max-width: 920px; }
    details { background: var(--white); border: 1px solid var(--line); border-radius: 8px; padding: 0 20px; }
    summary { cursor: pointer; padding: 18px 0; font-weight: 800; list-style: none; }
    summary::-webkit-details-marker { display: none; }
    summary:after { content: "+"; float: right; color: var(--blue); font-size: 22px; line-height: 1; }
    details[open] summary:after { content: "−"; }
    details p { padding: 0 0 18px; margin-bottom: 0; color: var(--muted); }
    .article-card { padding: 22px; }
    .article-card a { color: var(--blue); font-weight: 700; font-size: 14px; }
    .form-box { padding: 30px; background: var(--white); border: 1px solid var(--line); border-radius: 13px; box-shadow: var(--shadow); }
    .form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 15px; }
    label { display: grid; gap: 7px; color: #455064; font-size: 14px; font-weight: 700; }
    input, select, textarea {
      width: 100%;
      border: 1px solid #d9deea;
      border-radius: 6px;
      padding: 12px 13px;
      color: var(--ink);
      background: #fbfcfe;
      font: inherit;
    }
    textarea { min-height: 130px; resize: vertical; }
    .full { grid-column: 1 / -1; }
    .contact-info { display: grid; gap: 16px; }
    .contact-line { padding: 18px; background: var(--white); border-left: 4px solid var(--coral); }
    .contact-line strong { display: block; margin-bottom: 4px; }
    .qr { width: 150px; border: 7px solid var(--white); box-shadow: var(--shadow); }
    .footer {
      padding: 48px 0 22px;
      color: #e9edff;
      background: #19233a;
    }
    .footer-grid { display: grid; grid-template-columns: 1.1fr .9fr 1fr; gap: 35px; }
    .footer h3 { color: #fff; font-size: 18px; }
    .footer p, .footer a { color: #bbc5df; font-size: 14px; }
    .footer-links { display: flex; flex-wrap: wrap; gap: 8px 18px; }
    .copyright { margin-top: 34px; padding-top: 18px; border-top: 1px solid #37425b; color: #99a6c4; font-size: 13px; }
    .float-contact, .to-top {
      position: fixed;
      right: 22px;
      z-index: 15;
      border: 0;
      cursor: pointer;
      box-shadow: 0 10px 28px rgba(22,34,62,.18);
    }
    .float-contact {
      bottom: 78px;
      width: 52px;
      height: 52px;
      border-radius: 50%;
      background: var(--coral);
      color: #fff;
      font-size: 22px;
    }
    .qr-pop {
      display: none;
      position: fixed;
      right: 86px;
      bottom: 75px;
      z-index: 16;
      width: 180px;
      padding: 12px;
      background: #fff;
      border: 1px solid var(--line);
      box-shadow: var(--shadow);
    }
    .qr-pop.show { display: block; animation: pop .2s ease; }
    .qr-pop p { margin: 8px 0 0; font-size: 12px; text-align: center; }
    .to-top { display: none; bottom: 20px; width: 38px; height: 38px; border-radius: 6px; background: var(--blue); color: #fff; }
    .to-top.show { display: block; }
    .reveal { opacity: 0; transform: translateY(18px); transition: opacity .65s ease, transform .65s ease; }
    .reveal.visible { opacity: 1; transform: translateY(0); }
    @keyframes pop { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }
    @media (max-width: 1050px) {
      .nav-links a { padding-left: 7px; padding-right: 7px; font-size: 13px; }
      .service-grid { grid-template-columns: repeat(3, 1fr); }
      .process { grid-template-columns: repeat(3, 1fr); gap: 12px; }
      .step:not(:last-child):after { display: none; }
    }
    @media (max-width: 780px) {
      :root { --container: min(100% - 28px, 620px); }
      .nav { min-height: 66px; }
      .menu-toggle { display: block; }
      .nav-links {
        display: none;
        position: absolute;
        left: 14px;
        right: 14px;
        top: 66px;
        padding: 12px;
        background: var(--white);
        border: 1px solid var(--line);
        box-shadow: var(--shadow);
        border-radius: 8px;
      }
      .nav-links.open { display: grid; grid-template-columns: 1fr 1fr; }
      .nav-links a { padding: 10px; }
      .nav-cta { grid-column: 1 / -1; margin-top: 6px; }
      .hero { padding: 62px 0 54px; }
      .hero-grid, .about-grid, .contact-grid, .network-grid { grid-template-columns: 1fr; gap: 30px; }
      .hero-panel { transform: none; }
      .hero-panel-inner { transform: none; }
      h1 { font-size: clamp(38px, 12vw, 58px); }
      .metrics { grid-template-columns: repeat(2, 1fr); }
      .service-grid, .solution-grid, .case-grid, .review-grid, .article-grid { grid-template-columns: 1fr 1fr; }
      .process { grid-template-columns: 1fr 1fr; }
      .footer-grid { grid-template-columns: 1fr; gap: 20px; }
    }
    @media (max-width: 500px) {
      .section { padding: 62px 0; }
      .service-grid, .solution-grid, .case-grid, .review-grid, .article-grid, .process, .form-grid { grid-template-columns: 1fr; }
      .full { grid-column: auto; }
      .metrics { gap: 8px; }
      .metric { padding: 20px 13px; }
      .metric strong { font-size: 26px; }
      .rating-box { align-items: flex-start; flex-direction: column; gap: 10px; }
      .timeline-item { grid-template-columns: 1fr; gap: 5px; }
      .float-contact { right: 14px; }
      .qr-pop { right: 76px; }
    }