:root {
      --ink: #172033;
      --muted: #657089;
      --line: #dbe5f2;
      --paper: #f7fbff;
      --white: #ffffff;
      --blue: #1769ff;
      --cyan: #13b8c8;
      --green: #28b77a;
      --yellow: #ffc83d;
      --orange: #ff8652;
      --navy: #112b56;
      --shadow: 0 18px 45px rgba(31, 70, 125, .11);
      --radius: 18px;
    }

    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      color: var(--ink);
      background: var(--paper);
      font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", Arial, 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: min(1180px, calc(100% - 36px));
      margin: 0 auto;
    }
    .site-header {
      position: sticky;
      top: 0;
      z-index: 20;
      background: rgba(255,255,255,.94);
      border-bottom: 1px solid rgba(219,229,242,.9);
      backdrop-filter: blur(12px);
    }
    .nav-bar {
      min-height: 74px;
      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: #526078;
      font-size: 14px;
      padding: 8px 10px;
      transition: color .2s ease, background .2s ease;
    }
    .nav-links a:hover { color: var(--blue); background: #eef5ff; }
    .nav-cta, .button-primary {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      color: #fff;
      background: var(--blue);
      border: 1px solid var(--blue);
      border-radius: 9px;
      padding: 11px 18px;
      font-weight: 700;
      box-shadow: 0 8px 18px rgba(23,105,255,.2);
      transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
    }
    .nav-cta:hover, .button-primary:hover { transform: translateY(-2px); box-shadow: 0 12px 24px rgba(23,105,255,.28); }
    .button-secondary {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: var(--blue);
      background: #fff;
      border: 1px solid #bfd3f6;
      border-radius: 9px;
      padding: 11px 18px;
      font-weight: 700;
      transition: background .2s ease, transform .2s ease;
    }
    .button-secondary:hover { background: #eef5ff; transform: translateY(-2px); }
    .menu-toggle {
      display: none;
      border: 1px solid var(--line);
      background: #fff;
      border-radius: 8px;
      padding: 8px 11px;
      color: var(--ink);
      cursor: pointer;
    }
    .hero {
      position: relative;
      overflow: hidden;
      background:
        linear-gradient(135deg, #eaf5ff 0%, #f9fdff 45%, #e7fff7 100%);
      padding: 82px 0 68px;
      border-bottom: 1px solid #dceaf3;
    }
    .hero:before, .hero:after {
      content: "";
      position: absolute;
      border-radius: 50%;
      pointer-events: none;
      opacity: .65;
    }
    .hero:before {
      width: 350px;
      height: 350px;
      right: -130px;
      top: -100px;
      background: rgba(23,105,255,.13);
    }
    .hero:after {
      width: 250px;
      height: 250px;
      left: -100px;
      bottom: -130px;
      background: rgba(19,184,200,.13);
    }
    .hero-grid {
      position: relative;
      z-index: 1;
      display: grid;
      grid-template-columns: minmax(0, 1.12fr) minmax(320px, .88fr);
      gap: 56px;
      align-items: center;
    }
    .eyebrow {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      color: #087f99;
      font-size: 13px;
      font-weight: 800;
      letter-spacing: .08em;
      margin-bottom: 16px;
    }
    .eyebrow:before {
      content: "";
      width: 28px;
      height: 3px;
      background: var(--cyan);
      border-radius: 10px;
    }
    h1, h2, h3, p { margin-top: 0; }
    h1 {
      max-width: 650px;
      margin-bottom: 20px;
      color: var(--navy);
      font-size: clamp(36px, 5vw, 64px);
      line-height: 1.14;
      letter-spacing: 0;
    }
    .hero-copy {
      max-width: 650px;
      color: #53627a;
      font-size: 18px;
      margin-bottom: 30px;
    }
    .hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }
    .hero-note { margin: 20px 0 0; color: #6d7b91; font-size: 13px; }
    .hero-panel {
      background: rgba(255,255,255,.78);
      border: 1px solid rgba(190,213,238,.9);
      border-radius: 22px;
      padding: 25px;
      box-shadow: var(--shadow);
      animation: rise .7s ease both;
    }
    .panel-top {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding-bottom: 18px;
      border-bottom: 1px solid var(--line);
      margin-bottom: 18px;
    }
    .panel-label { color: var(--navy); font-weight: 800; }
    .status {
      color: #087d5d;
      background: #dff8ed;
      padding: 4px 9px;
      border-radius: 999px;
      font-size: 12px;
      font-weight: 700;
    }
    .flow-preview { display: grid; gap: 12px; }
    .flow-line {
      display: grid;
      grid-template-columns: 34px 1fr;
      gap: 12px;
      align-items: center;
    }
    .flow-icon {
      display: grid;
      place-items: center;
      width: 34px;
      height: 34px;
      border-radius: 10px;
      color: #fff;
      background: var(--blue);
      font-weight: 800;
      font-size: 13px;
    }
    .flow-line:nth-child(2) .flow-icon { background: var(--cyan); }
    .flow-line:nth-child(3) .flow-icon { background: var(--orange); }
    .flow-line:nth-child(4) .flow-icon { background: var(--green); }
    .flow-text strong { display: block; color: var(--ink); font-size: 14px; }
    .flow-text span { color: var(--muted); font-size: 12px; }
    .section { padding: 84px 0; }
    .section-alt { background: #fff; }
    .section-heading { max-width: 720px; margin-bottom: 34px; }
    .section-heading h2 {
      color: var(--navy);
      margin-bottom: 12px;
      font-size: clamp(28px, 4vw, 42px);
      line-height: 1.22;
      letter-spacing: 0;
    }
    .section-heading p { color: var(--muted); margin-bottom: 0; }
    .section-heading.center { margin-left: auto; margin-right: auto; text-align: center; }
    .stats {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 14px;
      margin-top: 38px;
    }
    .stat-card {
      background: #fff;
      border: 1px solid var(--line);
      border-top: 4px solid var(--blue);
      padding: 22px;
      border-radius: 12px;
      transition: transform .2s ease, box-shadow .2s ease;
    }
    .stat-card:hover, .service-card:hover, .review-card:hover, .case-card:hover { transform: translateY(-4px); box-shadow: var(--shadow); }
    .stat-card:nth-child(2) { border-top-color: var(--cyan); }
    .stat-card:nth-child(3) { border-top-color: var(--orange); }
    .stat-card:nth-child(4) { border-top-color: var(--green); }
    .stat-value { color: var(--navy); font-size: 28px; font-weight: 900; }
    .stat-label { color: var(--muted); font-size: 13px; }
    .intro-grid {
      display: grid;
      grid-template-columns: .9fr 1.1fr;
      gap: 46px;
      align-items: start;
    }
    .intro-lead { color: #40516c; font-size: 18px; }
    .feature-list {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 16px;
    }
    .feature-item {
      border-left: 3px solid var(--cyan);
      padding: 3px 0 3px 16px;
    }
    .feature-item strong { display: block; color: var(--navy); margin-bottom: 4px; }
    .feature-item span { color: var(--muted); font-size: 14px; }
    .service-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
    }
    .service-card {
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 14px;
      padding: 21px;
      transition: transform .2s ease, box-shadow .2s ease;
    }
    .service-number { color: var(--blue); font-size: 13px; font-weight: 800; }
    .service-card h3 { color: var(--navy); font-size: 18px; margin: 12px 0 8px; }
    .service-card p { color: var(--muted); font-size: 14px; margin-bottom: 0; }
    .service-tags, .tag-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
    }
    .service-tags { margin-top: 15px; }
    .tag {
      color: #2560a1;
      background: #eff7ff;
      border: 1px solid #d7eaff;
      padding: 4px 9px;
      border-radius: 999px;
      font-size: 12px;
    }
    .workflow {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 0;
      position: relative;
    }
    .workflow:before {
      content: "";
      position: absolute;
      top: 23px;
      left: 8%;
      right: 8%;
      height: 2px;
      background: #b9d8f2;
    }
    .step { position: relative; text-align: center; padding: 0 12px; }
    .step-index {
      position: relative;
      z-index: 1;
      display: grid;
      place-items: center;
      width: 48px;
      height: 48px;
      margin: 0 auto 16px;
      color: #fff;
      background: var(--blue);
      border: 6px solid #e4f1ff;
      border-radius: 50%;
      font-weight: 800;
    }
    .step:nth-child(2) .step-index { background: var(--cyan); }
    .step:nth-child(3) .step-index { background: var(--orange); }
    .step:nth-child(4) .step-index { background: #8e6ce8; }
    .step:nth-child(5) .step-index { background: var(--green); }
    .step h3 { color: var(--navy); font-size: 16px; margin-bottom: 6px; }
    .step p { color: var(--muted); font-size: 13px; }
    .solution-layout {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 22px;
    }
    .solution-panel {
      background: #f5faff;
      border: 1px solid #dceafa;
      border-radius: 16px;
      padding: 25px;
    }
    .solution-panel h3 { color: var(--navy); margin-bottom: 16px; }
    .solution-list { display: grid; gap: 10px; margin: 0; padding: 0; list-style: none; }
    .solution-list li { color: #53627a; padding-left: 23px; position: relative; font-size: 14px; }
    .solution-list li:before { content: "✓"; position: absolute; left: 0; color: var(--green); font-weight: 800; }
    .network {
      display: grid;
      grid-template-columns: 1fr 1.2fr;
      gap: 30px;
      align-items: center;
    }
    .network-copy {
      background: var(--navy);
      color: #fff;
      border-radius: 18px;
      padding: 30px;
    }
    .network-copy h2 { font-size: 30px; line-height: 1.25; margin-bottom: 12px; }
    .network-copy p { color: #d8e7fb; }
    .network-pills { display: flex; flex-wrap: wrap; gap: 9px; }
    .network-pills span {
      color: #eaf4ff;
      border: 1px solid rgba(255,255,255,.28);
      padding: 6px 10px;
      border-radius: 999px;
      font-size: 13px;
    }
    .tag-cloud { align-content: center; gap: 10px; }
    .tag-cloud .tag:nth-child(3n) { color: #8b4f16; background: #fff3d9; border-color: #ffe1a2; }
    .tag-cloud .tag:nth-child(4n) { color: #087d5d; background: #e4f9ef; border-color: #bfead5; }
    .case-grid, .review-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 18px;
    }
    .case-card, .review-card {
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 14px;
      overflow: hidden;
      transition: transform .2s ease, box-shadow .2s ease;
    }
    .case-media {
      aspect-ratio: 16 / 9;
      overflow: hidden;
      background: #eaf4ff;
    }
    .case-media img { width: 100%; height: 100%; object-fit: cover; }
    .case-body, .review-body { padding: 20px; }
    .case-body h3, .review-body h3 { color: var(--navy); font-size: 18px; margin-bottom: 7px; }
    .case-body p, .review-body p { color: var(--muted); font-size: 14px; margin-bottom: 0; }
    .review-card { padding: 0; }
    .review-body { min-height: 190px; }
    .review-meta { color: var(--blue); font-size: 13px; font-weight: 700; margin-bottom: 12px; }
    .stars { color: #f5a623; letter-spacing: 2px; margin-bottom: 10px; }
    .comparison-wrap { overflow-x: auto; background: #fff; border: 1px solid var(--line); border-radius: 14px; }
    .comparison {
      width: 100%;
      min-width: 760px;
      border-collapse: collapse;
    }
    .comparison th, .comparison td { padding: 16px 18px; border-bottom: 1px solid var(--line); text-align: left; }
    .comparison th { color: #fff; background: var(--navy); font-size: 14px; }
    .comparison td { color: var(--muted); font-size: 14px; }
    .comparison tr:last-child td { border-bottom: 0; }
    .comparison td:first-child { color: var(--ink); font-weight: 800; width: 24%; }
    .rating-box {
      display: flex;
      align-items: center;
      gap: 18px;
      margin-top: 22px;
      padding: 18px 22px;
      color: #744b00;
      background: #fff7df;
      border: 1px solid #f4d785;
      border-radius: 12px;
    }
    .rating-number { color: #d47a00; font-size: 34px; font-weight: 900; }
    .article-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 15px;
    }
    .article-item {
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 11px;
      padding: 17px;
      transition: border-color .2s ease, transform .2s ease;
    }
    .article-item:hover { border-color: #9ec4f5; transform: translateY(-3px); }
    .article-item small { color: var(--cyan); font-weight: 700; }
    .article-item h3 { color: var(--navy); font-size: 16px; margin: 8px 0 0; }
    .faq-list { display: grid; gap: 10px; max-width: 900px; margin: 0 auto; }
    .faq-item {
      background: #fff;
      border: 1px solid var(--line);
      border-radius: 10px;
      overflow: hidden;
    }
    .faq-item summary {
      cursor: pointer;
      list-style: none;
      padding: 17px 20px;
      color: var(--navy);
      font-weight: 800;
      position: relative;
      padding-right: 46px;
    }
    .faq-item summary::-webkit-details-marker { display: none; }
    .faq-item summary:after { content: "+"; position: absolute; right: 20px; color: var(--blue); font-size: 22px; font-weight: 400; }
    .faq-item[open] summary:after { content: "−"; }
    .faq-answer { padding: 0 20px 18px; color: var(--muted); font-size: 14px; }
    .contact-grid {
      display: grid;
      grid-template-columns: .8fr 1.2fr;
      gap: 28px;
      align-items: start;
    }
    .contact-info {
      background: #eaf5ff;
      border: 1px solid #cae1f6;
      border-radius: 16px;
      padding: 27px;
    }
    .contact-info h2 { color: var(--navy); font-size: 30px; line-height: 1.25; }
    .contact-info p { color: var(--muted); }
    .contact-lines { display: grid; gap: 12px; margin-top: 22px; }
    .contact-line { color: #40516c; font-size: 14px; }
    .contact-line strong { color: var(--navy); display: inline-block; min-width: 76px; }
    .qr {
      width: 120px;
      margin-top: 18px;
      border: 6px solid #fff;
      box-shadow: 0 5px 16px rgba(31,70,125,.12);
    }
    .form-card { background: #fff; border: 1px solid var(--line); border-radius: 16px; padding: 27px; }
    .form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 15px; }
    .field { display: grid; gap: 7px; }
    .field.full { grid-column: 1 / -1; }
    .field label { color: var(--navy); font-size: 13px; font-weight: 800; }
    .field input, .field select, .field textarea {
      width: 100%;
      border: 1px solid #cbd9ea;
      border-radius: 8px;
      padding: 11px 12px;
      color: var(--ink);
      background: #fbfdff;
      outline: none;
      transition: border-color .2s ease, box-shadow .2s ease;
    }
    .field textarea { min-height: 125px; resize: vertical; }
    .field input:focus, .field select:focus, .field textarea:focus { border-color: var(--blue); box-shadow: 0 0 0 3px rgba(23,105,255,.1); }
    .form-submit { margin-top: 18px; }
    .footer {
      color: #dbe8f7;
      background: #10294e;
      padding: 42px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 1.2fr .8fr .8fr;
      gap: 30px;
      padding-bottom: 30px;
      border-bottom: 1px solid rgba(255,255,255,.16);
    }
    .footer h3 { color: #fff; font-size: 18px; margin-bottom: 12px; }
    .footer p, .footer a { color: #b9cbe1; font-size: 13px; }
    .footer a:hover { color: #fff; }
    .footer-links { display: grid; gap: 7px; }
    .copyright { color: #9eb4ce; font-size: 12px; padding-top: 18px; }
    .floating {
      position: fixed;
      right: 18px;
      bottom: 20px;
      z-index: 15;
      display: grid;
      gap: 8px;
    }
    .floating a {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      background: var(--blue);
      border-radius: 999px;
      padding: 10px 15px;
      font-size: 13px;
      font-weight: 800;
      box-shadow: 0 9px 22px rgba(23,105,255,.27);
    }
    .floating a:last-child { background: var(--green); }
    .reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s ease, transform .6s ease; }
    .reveal.is-visible { opacity: 1; transform: translateY(0); }
    @keyframes rise { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: translateY(0); } }

    @media (max-width: 1020px) {
      .nav-links a { padding-left: 7px; padding-right: 7px; font-size: 13px; }
      .service-grid { grid-template-columns: repeat(2, 1fr); }
      .hero-grid, .intro-grid, .network, .contact-grid { grid-template-columns: 1fr; }
      .hero-grid { gap: 34px; }
      .hero-panel { max-width: 620px; }
      .stats { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 760px) {
      .container { width: min(100% - 28px, 620px); }
      .nav-bar { min-height: 66px; }
      .menu-toggle { display: inline-block; }
      .nav-cta { display: none; }
      .nav-links {
        display: none;
        position: absolute;
        top: 66px;
        left: 0;
        right: 0;
        padding: 10px 14px 16px;
        background: #fff;
        border-bottom: 1px solid var(--line);
        box-shadow: 0 12px 20px rgba(24,52,94,.08);
        justify-content: flex-start;
      }
      .nav-links.is-open { display: grid; grid-template-columns: repeat(2, 1fr); }
      .nav-links a { padding: 9px 8px; }
      .hero { padding: 60px 0 48px; }
      h1 { font-size: 38px; }
      .hero-copy { font-size: 16px; }
      .section { padding: 58px 0; }
      .feature-list, .solution-layout, .case-grid, .review-grid, .article-grid { grid-template-columns: 1fr; }
      .service-grid { grid-template-columns: 1fr; }
      .stats { gap: 10px; }
      .stat-card { padding: 17px; }
      .workflow { grid-template-columns: 1fr; gap: 19px; }
      .workflow:before { top: 0; bottom: 0; left: 24px; width: 2px; height: auto; }
      .step { display: grid; grid-template-columns: 48px 1fr; gap: 14px; text-align: left; align-items: center; padding: 0; }
      .step-index { margin: 0; }
      .step p { grid-column: 2; margin-top: -17px; }
      .form-grid { grid-template-columns: 1fr; }
      .field.full { grid-column: auto; }
      .footer-grid { grid-template-columns: 1fr; gap: 20px; }
      .floating { right: 10px; bottom: 12px; }
    }