:root {
      --ink: #172033;
      --muted: #5c6678;
      --line: #dfe5ef;
      --paper: #ffffff;
      --soft: #f5f8fc;
      --blue: #315df5;
      --cyan: #13b7b1;
      --coral: #ef695c;
      --yellow: #f5bb4d;
      --violet: #7967e8;
      --shadow: 0 16px 40px rgba(36, 55, 96, .10);
      --container: min(1180px, calc(100% - 40px));
    }

    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      color: var(--ink);
      background:
        linear-gradient(180deg, #fbfdff 0%, #f8fbff 42%, #ffffff 100%);
      font-family: "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
      line-height: 1.7;
    }
    a { color: inherit; text-decoration: none; }
    button, input, select, textarea { font: inherit; }
    img { max-width: 100%; height: auto; display: block; }
    .container { width: var(--container); margin: 0 auto; }
    .site-header {
      position: sticky;
      top: 0;
      z-index: 20;
      background: rgba(255,255,255,.94);
      border-bottom: 1px solid rgba(223,229,239,.9);
      backdrop-filter: blur(16px);
    }
    .nav-bar {
      min-height: 76px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 18px;
    }
    .brand {
      display: inline-flex;
      align-items: center;
      gap: 10px;
      flex: 0 0 auto;
      font-weight: 800;
      color: var(--ink);
      letter-spacing: .02em;
    }
    .ai-page-logo { width: 40px; border-radius: 10px; }
    .brand-name { font-size: 18px; }
    .nav-links {
      display: flex;
      align-items: center;
      justify-content: flex-end;
      gap: 0;
      flex-wrap: wrap;
    }
    .nav-links a {
      color: #4d5970;
      font-size: 13px;
      padding: 8px 9px;
      border-radius: 7px;
      transition: color .2s ease, background .2s ease;
    }
    .nav-links a:hover { color: var(--blue); background: #edf2ff; }
    .nav-cta, .primary-btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border: 0;
      cursor: pointer;
      color: #fff;
      background: var(--blue);
      box-shadow: 0 8px 18px rgba(49,93,245,.22);
      border-radius: 8px;
      padding: 11px 18px;
      font-weight: 700;
      transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
    }
    .nav-cta { margin-left: 12px; padding: 9px 15px; font-size: 13px; }
    .nav-cta:hover, .primary-btn:hover { transform: translateY(-2px); box-shadow: 0 12px 24px rgba(49,93,245,.28); }
    .menu-toggle { display: none; border: 0; background: transparent; color: var(--ink); font-size: 24px; cursor: pointer; }

    .hero {
      position: relative;
      overflow: hidden;
      padding: 96px 0 76px;
      background:
        linear-gradient(135deg, #f7f9ff 0%, #eef8ff 52%, #fff8ed 100%);
      border-bottom: 1px solid #e8edf5;
    }
    .hero::before, .hero::after {
      content: "";
      position: absolute;
      border-radius: 50%;
      pointer-events: none;
      filter: blur(1px);
    }
    .hero::before {
      width: 360px;
      height: 360px;
      right: -110px;
      top: -160px;
      background: rgba(49,93,245,.12);
    }
    .hero::after {
      width: 240px;
      height: 240px;
      left: -100px;
      bottom: -130px;
      background: rgba(239,105,92,.12);
    }
    .hero-grid {
      position: relative;
      z-index: 1;
      display: grid;
      grid-template-columns: minmax(0, 1.15fr) minmax(300px, .85fr);
      gap: 54px;
      align-items: center;
    }
    .eyebrow, .section-kicker {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      color: var(--blue);
      font-size: 13px;
      font-weight: 800;
      letter-spacing: .08em;
    }
    .eyebrow::before, .section-kicker::before {
      content: "";
      width: 26px;
      height: 3px;
      border-radius: 3px;
      background: linear-gradient(90deg, var(--coral), var(--yellow), var(--cyan));
    }
    h1, h2, h3, p { margin-top: 0; }
    h1 {
      max-width: 720px;
      margin-bottom: 22px;
      font-size: clamp(36px, 5vw, 68px);
      line-height: 1.12;
      letter-spacing: 0;
    }
    .hero-copy {
      max-width: 650px;
      color: var(--muted);
      font-size: 18px;
      margin-bottom: 30px;
    }
    .hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
    .secondary-btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border: 1px solid #cbd5e6;
      color: var(--ink);
      background: rgba(255,255,255,.7);
      border-radius: 8px;
      padding: 10px 18px;
      font-weight: 700;
      transition: border-color .2s ease, transform .2s ease, background .2s ease;
    }
    .secondary-btn:hover { border-color: var(--blue); transform: translateY(-2px); background: #fff; }
    .hero-panel {
      position: relative;
      padding: 26px;
      background: rgba(255,255,255,.78);
      border: 1px solid rgba(255,255,255,.95);
      box-shadow: var(--shadow);
      border-radius: 18px;
    }
    .hero-panel h2 { font-size: 20px; margin-bottom: 14px; }
    .mini-flow { display: grid; gap: 12px; }
    .mini-flow-item {
      display: flex;
      gap: 12px;
      align-items: center;
      padding: 13px 14px;
      background: #fff;
      border: 1px solid #e6ebf3;
      border-radius: 10px;
    }
    .flow-num {
      display: grid;
      place-items: center;
      width: 30px;
      height: 30px;
      flex: 0 0 30px;
      border-radius: 50%;
      color: #fff;
      background: var(--coral);
      font-weight: 800;
      font-size: 13px;
    }
    .mini-flow-item:nth-child(2) .flow-num { background: var(--cyan); }
    .mini-flow-item:nth-child(3) .flow-num { background: var(--violet); }
    .mini-flow-item strong { display: block; font-size: 14px; }
    .mini-flow-item small { color: var(--muted); font-size: 12px; }

    .section { padding: 84px 0; }
    .section-tint { background: #f5f8fd; }
    .section-head {
      max-width: 760px;
      margin-bottom: 34px;
    }
    .section-head h2 {
      margin: 10px 0 12px;
      font-size: clamp(28px, 4vw, 42px);
      line-height: 1.2;
    }
    .section-head p { color: var(--muted); margin-bottom: 0; }
    .metric-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 14px;
    }
    .metric {
      padding: 24px 20px;
      background: #fff;
      border: 1px solid var(--line);
      border-top: 4px solid var(--blue);
      border-radius: 8px;
      box-shadow: 0 8px 24px rgba(45,62,99,.05);
    }
    .metric:nth-child(2) { border-top-color: var(--coral); }
    .metric:nth-child(3) { border-top-color: var(--cyan); }
    .metric:nth-child(4) { border-top-color: var(--yellow); }
    .metric strong { display: block; font-size: 30px; line-height: 1.1; margin-bottom: 7px; }
    .metric span { color: var(--muted); font-size: 14px; }

    .about-layout, .contact-layout {
      display: grid;
      grid-template-columns: 1.05fr .95fr;
      gap: 44px;
      align-items: start;
    }
    .about-copy p { color: var(--muted); }
    .highlight-list { display: grid; gap: 13px; margin: 24px 0 0; padding: 0; list-style: none; }
    .highlight-list li { padding-left: 30px; position: relative; color: #344056; }
    .highlight-list li::before {
      content: "✓";
      position: absolute;
      left: 0;
      top: 2px;
      width: 20px;
      height: 20px;
      display: grid;
      place-items: center;
      border-radius: 50%;
      color: #fff;
      background: var(--cyan);
      font-size: 12px;
      font-weight: 800;
    }
    .about-aside {
      padding: 26px;
      background: #172033;
      color: #fff;
      border-radius: 16px;
      box-shadow: var(--shadow);
    }
    .about-aside h3 { margin-bottom: 16px; font-size: 22px; }
    .about-aside p { color: #cdd7e7; }
    .tag-cloud { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 22px; }
    .tag-cloud span {
      padding: 6px 10px;
      color: #e9efff;
      border: 1px solid rgba(255,255,255,.22);
      border-radius: 999px;
      font-size: 12px;
    }

    .service-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
    }
    .service-card {
      padding: 22px;
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 12px;
      transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
    }
    .service-card:hover { transform: translateY(-5px); box-shadow: var(--shadow); border-color: #b8c8f5; }
    .service-icon {
      display: grid;
      place-items: center;
      width: 42px;
      height: 42px;
      margin-bottom: 17px;
      color: #fff;
      border-radius: 10px;
      background: linear-gradient(135deg, var(--blue), var(--violet));
      font-weight: 800;
    }
    .service-card:nth-child(2n) .service-icon { background: linear-gradient(135deg, var(--coral), var(--yellow)); }
    .service-card:nth-child(3n) .service-icon { background: linear-gradient(135deg, var(--cyan), #4d8df7); }
    .service-card h3 { margin-bottom: 8px; font-size: 18px; }
    .service-card p { color: var(--muted); font-size: 14px; margin-bottom: 0; }

    .workflow {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 0;
      border: 1px solid var(--line);
      background: #fff;
      border-radius: 14px;
      overflow: hidden;
    }
    .workflow-step {
      position: relative;
      padding: 25px 20px;
      border-right: 1px solid var(--line);
    }
    .workflow-step:last-child { border-right: 0; }
    .workflow-step strong { display: block; font-size: 17px; margin: 13px 0 7px; }
    .workflow-step p { color: var(--muted); font-size: 13px; margin: 0; }
    .step-label {
      display: inline-flex;
      padding: 4px 9px;
      color: var(--blue);
      background: #edf2ff;
      border-radius: 5px;
      font-size: 12px;
      font-weight: 800;
    }

    .industry-grid, .case-grid, .review-grid, .article-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 18px;
    }
    .industry-card, .review-card, .article-card {
      padding: 22px;
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 12px;
    }
    .industry-card h3 { font-size: 18px; margin-bottom: 9px; }
    .industry-card p, .review-card p, .article-card p { color: var(--muted); font-size: 14px; margin-bottom: 0; }
    .industry-card .industry-line { height: 4px; width: 56px; margin-bottom: 18px; border-radius: 4px; background: var(--coral); }
    .industry-card:nth-child(2) .industry-line { background: var(--cyan); }
    .industry-card:nth-child(3) .industry-line { background: var(--violet); }
    .industry-card:nth-child(4) .industry-line { background: var(--yellow); }
    .industry-card:nth-child(5) .industry-line { background: var(--blue); }
    .industry-card:nth-child(6) .industry-line { background: #43a876; }

    .network-band {
      display: grid;
      grid-template-columns: .9fr 1.1fr;
      gap: 36px;
      align-items: center;
      padding: 32px;
      color: #fff;
      border-radius: 18px;
      background: linear-gradient(125deg, #315df5, #7967e8 55%, #ef695c);
      box-shadow: var(--shadow);
    }
    .network-band h2 { margin-bottom: 10px; }
    .network-band p { color: #edf1ff; }
    .model-list { display: flex; flex-wrap: wrap; gap: 9px; }
    .model-list span {
      padding: 8px 11px;
      color: #fff;
      border: 1px solid rgba(255,255,255,.35);
      background: rgba(255,255,255,.12);
      border-radius: 7px;
      font-size: 13px;
    }

    .comparison-wrap {
      overflow-x: auto;
      border: 1px solid var(--line);
      border-radius: 12px;
      background: #fff;
    }
    .comparison {
      width: 100%;
      min-width: 760px;
      border-collapse: collapse;
    }
    .comparison th, .comparison td {
      padding: 17px 18px;
      text-align: left;
      border-bottom: 1px solid var(--line);
      vertical-align: top;
      font-size: 14px;
    }
    .comparison th { color: #fff; background: #263452; font-weight: 700; }
    .comparison th:nth-child(2) { background: var(--blue); }
    .comparison td:first-child { font-weight: 700; color: #2e3b56; }
    .comparison tr:last-child td { border-bottom: 0; }
    .rating {
      display: flex;
      align-items: center;
      gap: 10px;
      color: #c76a00;
      font-size: 22px;
      font-weight: 800;
    }
    .rating small { color: var(--muted); font-size: 13px; font-weight: 400; }

    .price-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 17px;
    }
    .price-card {
      padding: 25px;
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 12px;
    }
    .price-card.featured { border: 2px solid var(--blue); box-shadow: var(--shadow); }
    .price-card h3 { margin-bottom: 8px; }
    .price-card .price { font-size: 29px; font-weight: 800; color: var(--blue); margin: 10px 0 8px; }
    .price-card p { color: var(--muted); font-size: 14px; margin-bottom: 0; }

    .case-card {
      overflow: hidden;
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 12px;
    }
    .case-image { aspect-ratio: 16 / 9; overflow: hidden; background: #eaf0f8; }
    .case-image img { width: 100%; height: 100%; object-fit: cover; }
    .case-content { padding: 19px 20px 22px; }
    .case-content h3 { margin-bottom: 7px; font-size: 18px; }
    .case-content p { color: var(--muted); font-size: 14px; margin: 0; }

    .review-card { position: relative; }
    .review-card::before {
      content: "“";
      position: absolute;
      top: 7px;
      right: 18px;
      color: #dbe4ff;
      font-family: Georgia, serif;
      font-size: 58px;
      line-height: 1;
    }
    .review-stars { color: #e9a52c; letter-spacing: 2px; margin-bottom: 11px; }
    .review-card p { min-height: 78px; }
    .review-user { display: flex; align-items: center; gap: 10px; margin-top: 17px; }
    .avatar {
      display: grid;
      place-items: center;
      width: 34px;
      height: 34px;
      border-radius: 50%;
      color: #fff;
      background: var(--blue);
      font-weight: 800;
      font-size: 13px;
    }
    .review-user strong { display: block; font-size: 13px; }
    .review-user span { display: block; color: var(--muted); font-size: 12px; }

    .faq-list { display: grid; gap: 10px; max-width: 920px; }
    details {
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 9px;
      padding: 0 20px;
    }
    summary {
      cursor: pointer;
      padding: 17px 28px 17px 0;
      position: relative;
      list-style: none;
      font-weight: 700;
    }
    summary::-webkit-details-marker { display: none; }
    summary::after {
      content: "+";
      position: absolute;
      right: 0;
      top: 14px;
      color: var(--blue);
      font-size: 22px;
      font-weight: 400;
    }
    details[open] summary::after { content: "−"; }
    details p { color: var(--muted); font-size: 14px; padding: 0 0 17px; margin: 0; }

    .article-card { transition: transform .2s ease, border-color .2s ease; }
    .article-card:hover { transform: translateY(-3px); border-color: #b8c8f5; }
    .article-meta { display: block; color: var(--blue); font-size: 12px; margin-bottom: 11px; }
    .article-card h3 { font-size: 17px; margin-bottom: 7px; }
    .article-card a { display: inline-block; margin-top: 15px; color: var(--blue); font-size: 13px; font-weight: 700; }

    .contact-layout { align-items: stretch; }
    .contact-panel {
      padding: 28px;
      color: #fff;
      background: #1d2940;
      border-radius: 15px;
    }
    .contact-panel h2 { font-size: 30px; margin-bottom: 12px; }
    .contact-panel p { color: #d4ddec; }
    .contact-info { display: grid; gap: 13px; margin-top: 24px; }
    .contact-info div { padding: 12px 14px; border: 1px solid rgba(255,255,255,.15); border-radius: 8px; }
    .contact-info strong { display: block; font-size: 13px; color: #aebbe0; }
    .contact-info span { display: block; margin-top: 3px; font-size: 15px; }
    .form-panel {
      padding: 28px;
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 15px;
    }
    .form-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 15px; }
    .field { display: grid; gap: 6px; }
    .field.full { grid-column: 1 / -1; }
    label { color: #39445a; font-size: 13px; font-weight: 700; }
    input, select, textarea {
      width: 100%;
      padding: 12px 13px;
      color: var(--ink);
      background: #fbfcfe;
      border: 1px solid #d6deeb;
      border-radius: 7px;
      outline: none;
      transition: border-color .2s ease, box-shadow .2s ease;
    }
    textarea { min-height: 130px; resize: vertical; }
    input:focus, select:focus, textarea:focus { border-color: var(--blue); box-shadow: 0 0 0 3px rgba(49,93,245,.12); }
    .form-submit { margin-top: 18px; }

    .visual-assets {
      display: grid;
      grid-template-columns: 1.4fr .8fr;
      gap: 18px;
      align-items: start;
    }
    .asset-wide, .asset-square {
      overflow: hidden;
      background: #eef2f8;
      border-radius: 13px;
      border: 1px solid var(--line);
    }
    .asset-wide img, .asset-square img { width: 100%; object-fit: cover; }
    .asset-wide img { aspect-ratio: 16 / 7; }
    .asset-square img { aspect-ratio: 1 / 1; }

    .footer {
      color: #d9e1ef;
      background: #172033;
      padding: 48px 0 24px;
    }
    .footer-main {
      display: grid;
      grid-template-columns: 1.25fr .75fr .9fr;
      gap: 34px;
      padding-bottom: 30px;
      border-bottom: 1px solid rgba(255,255,255,.14);
    }
    .footer h2, .footer h3 { color: #fff; }
    .footer h2 { font-size: 22px; margin-bottom: 12px; }
    .footer h3 { font-size: 15px; margin-bottom: 12px; }
    .footer p { color: #b5c1d6; font-size: 13px; }
    .footer-links { display: grid; gap: 6px; }
    .footer-links a { color: #cbd5e6; font-size: 13px; }
    .footer-links a:hover { color: #fff; }
    .footer-bottom {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 16px;
      padding-top: 20px;
      color: #9eacc2;
      font-size: 12px;
    }
    .floating-service {
      position: fixed;
      right: 20px;
      bottom: 22px;
      z-index: 15;
      display: grid;
      gap: 7px;
      justify-items: end;
    }
    .service-bubble {
      display: none;
      padding: 12px;
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 10px;
      box-shadow: var(--shadow);
    }
    .service-bubble img { width: 130px; }
    .float-btn {
      border: 0;
      cursor: pointer;
      padding: 12px 16px;
      color: #fff;
      background: var(--coral);
      border-radius: 999px;
      box-shadow: 0 8px 22px rgba(239,105,92,.32);
      font-weight: 800;
    }
    .float-btn.active + .service-bubble { display: block; }
    .back-top {
      position: fixed;
      right: 20px;
      bottom: 79px;
      width: 38px;
      height: 38px;
      border: 1px solid var(--line);
      border-radius: 50%;
      color: var(--blue);
      background: #fff;
      cursor: pointer;
      box-shadow: 0 6px 18px rgba(31,49,87,.12);
      opacity: 0;
      pointer-events: none;
      transition: opacity .2s ease;
    }
    .back-top.visible { opacity: 1; pointer-events: auto; }
    .reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s ease, transform .6s ease; }
    .reveal.show { opacity: 1; transform: translateY(0); }

    @media (max-width: 1040px) {
      .nav-links a { padding: 8px 6px; font-size: 12px; }
      .service-grid { grid-template-columns: repeat(3, 1fr); }
      .workflow { grid-template-columns: repeat(3, 1fr); }
      .workflow-step:nth-child(3) { border-right: 0; }
      .workflow-step:nth-child(-n+3) { border-bottom: 1px solid var(--line); }
    }
    @media (max-width: 820px) {
      :root { --container: min(100% - 28px, 680px); }
      .nav-bar { min-height: 68px; }
      .menu-toggle { display: block; }
      .nav-links {
        display: none;
        position: absolute;
        top: 68px;
        left: 14px;
        right: 14px;
        padding: 10px;
        align-items: stretch;
        background: #fff;
        border: 1px solid var(--line);
        border-radius: 10px;
        box-shadow: var(--shadow);
      }
      .nav-links.open { display: grid; }
      .nav-links a { padding: 10px 12px; }
      .nav-cta { margin: 6px 0 0; }
      .hero { padding: 65px 0 55px; }
      .hero-grid, .about-layout, .contact-layout, .network-band { grid-template-columns: 1fr; }
      .hero-panel { max-width: 580px; }
      .metric-grid, .service-grid { grid-template-columns: repeat(2, 1fr); }
      .industry-grid, .case-grid, .review-grid, .article-grid, .price-grid { grid-template-columns: repeat(2, 1fr); }
      .footer-main { grid-template-columns: 1fr 1fr; }
      .footer-main > div:first-child { grid-column: 1 / -1; }
    }
    @media (max-width: 560px) {
      :root { --container: calc(100% - 28px); }
      h1 { font-size: 39px; }
      .hero-copy { font-size: 16px; }
      .section { padding: 60px 0; }
      .metric-grid, .service-grid, .industry-grid, .case-grid, .review-grid, .article-grid, .price-grid, .form-grid { grid-template-columns: 1fr; }
      .workflow { grid-template-columns: 1fr; }
      .workflow-step, .workflow-step:nth-child(3) { border-right: 0; border-bottom: 1px solid var(--line); }
      .workflow-step:last-child { border-bottom: 0; }
      .footer-main { grid-template-columns: 1fr; }
      .footer-main > div:first-child { grid-column: auto; }
      .footer-bottom { align-items: flex-start; flex-direction: column; }
      .network-band { padding: 24px; }
      .contact-panel, .form-panel { padding: 22px; }
    }