/* roulang page: index */
:root {
      color-scheme: light;
      --ink: #172535;
      --muted: #647487;
      --blue: #1769aa;
      --blue-dark: #105184;
      --teal: #138b84;
      --paper: #ffffff;
      --canvas: #f5f8fc;
      --line: #e1e8f0;
      --soft-blue: #eaf4fc;
      --soft-teal: #e9f7f4;
      --soft-yellow: #fff7df;
      --shadow: 0 12px 34px rgba(27, 54, 81, .08);
      --shadow-hover: 0 18px 42px rgba(27, 54, 81, .14);
      --radius: 8px;
      --container: 1160px;
    }
    *, *::before, *::after { box-sizing: border-box; }
    html { scroll-behavior: smooth; scroll-padding-top: 92px; }
    body {
      margin: 0;
      color: var(--ink);
      background: var(--canvas);
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
      font-size: 16px;
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    a { color: inherit; text-decoration: none; }
    img { display: block; max-width: 100%; }
    button { font: inherit; }
    button, a { -webkit-tap-highlight-color: transparent; }
    a:focus-visible, button:focus-visible { outline: 3px solid rgba(23, 105, 170, .35); outline-offset: 3px; }
    .container { width: min(var(--container), calc(100% - 48px)); margin-inline: auto; }
    .site-header {
      position: sticky; top: 0; z-index: 20; background: rgba(255,255,255,.96);
      border-bottom: 1px solid var(--line); backdrop-filter: blur(14px);
    }
    .nav-wrap { min-height: 76px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
    .brand { display: inline-flex; align-items: center; gap: 11px; min-width: 0; font-weight: 750; }
    .brand-mark {
      width: 38px; height: 38px; display: grid; place-items: center; flex: 0 0 auto;
      border-radius: 8px; color: #fff; background: var(--blue); font-size: 18px;
      box-shadow: 0 6px 14px rgba(23,105,170,.2);
    }
    .brand-name { font-size: 16px; line-height: 1.25; }
    .nav-links { display: flex; align-items: center; gap: 25px; margin: 0; padding: 0; list-style: none; }
    .nav-links a { display: inline-flex; align-items: center; min-height: 42px; color: #506174; font-size: 14px; transition: color .2s ease; }
    .nav-links a:hover, .nav-links a.active { color: var(--blue); }
    .nav-links a.active { font-weight: 700; }
    .nav-links .nav-cta {
      min-height: 40px; padding: 0 16px; border-radius: 6px; color: #fff;
      background: var(--blue); font-weight: 650;
    }
    .nav-links .nav-cta:hover { color: #fff; background: var(--blue-dark); }
    .menu-toggle {
      display: none; width: 42px; height: 42px; border: 1px solid var(--line); border-radius: 6px;
      color: var(--ink); background: #fff; cursor: pointer;
    }
    .hero {
      position: relative; overflow: hidden; padding: 72px 0 60px;
      background: #eaf4fc;
      border-bottom: 1px solid #dce9f4;
    }
    .hero::after {
      content: ""; position: absolute; right: -90px; top: -150px; width: 470px; height: 470px;
      border: 1px solid rgba(23,105,170,.12); border-radius: 50%;
      box-shadow: 0 0 0 48px rgba(23,105,170,.035), 0 0 0 96px rgba(23,105,170,.025);
      pointer-events: none;
    }
    .hero-inner { position: relative; z-index: 1; max-width: 900px; }
    .eyebrow { display: inline-flex; align-items: center; gap: 8px; color: var(--blue); font-size: 13px; font-weight: 750; }
    .eyebrow::before { content: ""; width: 18px; height: 2px; background: var(--teal); }
    h1 { max-width: 820px; margin: 17px 0 12px; font-size: clamp(34px, 5vw, 54px); line-height: 1.2; font-weight: 780; }
    .hero-highlight { color: var(--blue); }
    .hero-subtitle { margin: 0 0 12px; color: #29435d; font-size: 20px; font-weight: 650; }
    .hero-copy { max-width: 790px; margin: 0; color: #52677b; font-size: 16px; }
    .hero-form {
      display: flex; align-items: center; gap: 10px; max-width: 670px; margin-top: 25px;
      padding: 8px; border: 1px solid #d5e2ed; border-radius: 8px; background: #fff;
      box-shadow: 0 10px 28px rgba(34,72,105,.08);
    }
    .hero-form input {
      width: 100%; min-width: 0; height: 46px; padding: 0 12px; border: 0; outline: none;
      color: var(--ink); background: transparent; font-size: 15px;
    }
    .hero-form input::placeholder { color: #8b99a8; }
    .button {
      display: inline-flex; align-items: center; justify-content: center; gap: 8px;
      min-height: 46px; padding: 0 18px; border: 1px solid transparent; border-radius: 6px;
      color: #fff; background: var(--blue); font-weight: 700; cursor: pointer;
      transition: transform .18s ease, background .18s ease, box-shadow .18s ease;
    }
    .button:hover { background: var(--blue-dark); box-shadow: 0 7px 16px rgba(23,105,170,.2); transform: translateY(-1px); }
    .button.secondary { color: var(--blue); border-color: #bfd5e7; background: #fff; }
    .button.secondary:hover { background: #f5fbff; }
    .hero-footnote { margin: 10px 0 0; color: #738396; font-size: 12px; }
    main { display: block; }
    .section { padding: 66px 0; border-bottom: 1px solid var(--line); }
    .section.white { background: var(--paper); }
    .section.tint { background: #f0f6fb; }
    .section-head { display: flex; align-items: end; justify-content: space-between; gap: 24px; margin-bottom: 27px; }
    .section-head h2 { max-width: 720px; margin: 0; font-size: 28px; line-height: 1.3; letter-spacing: 0; }
    .section-head p { max-width: 640px; margin: 9px 0 0; color: var(--muted); }
    .section-kicker { display: block; margin-bottom: 7px; color: var(--teal); font-size: 12px; font-weight: 750; }
    .text-link { display: inline-flex; align-items: center; gap: 7px; flex: 0 0 auto; color: var(--blue); font-size: 14px; font-weight: 700; }
    .text-link:hover { color: var(--blue-dark); }
    .collection-layout { display: grid; grid-template-columns: 1.15fr .85fr; gap: 24px; align-items: stretch; }
    .feature-panel {
      min-height: 290px; display: flex; flex-direction: column; justify-content: space-between;
      padding: 30px; border-radius: var(--radius); color: #fff; background: #1769aa;
      box-shadow: var(--shadow);
    }
    .feature-panel .panel-label { color: #c4e5fb; font-size: 13px; font-weight: 700; }
    .feature-panel h3 { max-width: 480px; margin: 25px 0 10px; font-size: 30px; line-height: 1.3; }
    .feature-panel p { max-width: 520px; margin: 0; color: #e2f0fb; }
    .panel-meta { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 25px; }
    .panel-meta span { padding: 5px 9px; border: 1px solid rgba(255,255,255,.28); border-radius: 4px; color: #eff8ff; font-size: 12px; }
    .directory { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .directory-item {
      display: flex; align-items: flex-start; gap: 13px; padding: 18px;
      border: 1px solid var(--line); border-radius: var(--radius); background: #fff;
      transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
    }
    .directory-item:hover { transform: translateY(-2px); border-color: #b9d3e7; box-shadow: var(--shadow); }
    .directory-icon {
      width: 36px; height: 36px; display: grid; place-items: center; flex: 0 0 auto;
      border-radius: 6px; color: var(--blue); background: var(--soft-blue); font-size: 14px; font-weight: 800;
    }
    .directory-item h3 { margin: 0 0 4px; font-size: 15px; }
    .directory-item p { margin: 0; color: var(--muted); font-size: 13px; line-height: 1.6; }
    .topic-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
    .topic-card {
      min-height: 172px; padding: 21px; border: 1px solid var(--line); border-radius: var(--radius);
      background: #fff; box-shadow: 0 5px 18px rgba(27,54,81,.035);
      transition: transform .2s ease, box-shadow .2s ease;
    }
    .topic-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-hover); }
    .topic-number { color: var(--teal); font-size: 12px; font-weight: 800; }
    .topic-card h3 { margin: 10px 0 6px; font-size: 17px; }
    .topic-card p { margin: 0; color: var(--muted); font-size: 13px; }
    .split-content { display: grid; grid-template-columns: .8fr 1.2fr; gap: 52px; align-items: center; }
    .split-content h2 { margin: 0 0 13px; font-size: 28px; line-height: 1.35; }
    .split-content > div > p { margin: 0; color: var(--muted); }
    .check-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; margin: 0; padding: 0; list-style: none; }
    .check-list li { display: flex; gap: 11px; padding: 15px; border: 1px solid var(--line); border-radius: 6px; background: #fff; }
    .check-mark { width: 21px; height: 21px; display: grid; place-items: center; flex: 0 0 auto; border-radius: 50%; color: #087b69; background: var(--soft-teal); font-size: 12px; font-weight: 800; }
    .check-list strong { display: block; margin-bottom: 3px; font-size: 14px; }
    .check-list span:last-child { color: var(--muted); font-size: 12px; }
    .steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; overflow: hidden; }
    .step { position: relative; padding: 25px; }
    .step + .step { border-left: 1px solid var(--line); }
    .step-index { display: inline-grid; width: 31px; height: 31px; place-items: center; border-radius: 50%; color: #fff; background: var(--teal); font-size: 13px; font-weight: 750; }
    .step h3 { margin: 13px 0 6px; font-size: 17px; }
    .step p { margin: 0; color: var(--muted); font-size: 14px; }
    .compare-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
    .compare { width: 100%; border-collapse: collapse; text-align: left; }
    .compare th, .compare td { padding: 15px 18px; border-bottom: 1px solid var(--line); }
    .compare th { color: #455a6d; background: #f3f7fa; font-size: 13px; }
    .compare td { color: #526477; font-size: 14px; }
    .compare td:first-child { color: var(--ink); font-weight: 650; }
    .compare tr:last-child td { border-bottom: 0; }
    .compare .good { color: #087b69; font-weight: 700; }
    .signal-row { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
    .signal { padding: 22px 0; border-top: 2px solid var(--blue); }
    .signal h3 { margin: 0 0 8px; font-size: 17px; }
    .signal p { margin: 0; color: var(--muted); font-size: 14px; }
    .news-layout { display: grid; grid-template-columns: .8fr 1.2fr; gap: 34px; }
    .news-intro { padding-right: 20px; }
    .news-intro h2 { margin: 0 0 11px; font-size: 27px; line-height: 1.35; }
    .news-intro p { margin: 0; color: var(--muted); }
    .news-list { margin: 0; padding: 0; list-style: none; border-top: 1px solid var(--line); }
    .news-list li { display: grid; grid-template-columns: 100px 1fr auto; align-items: center; gap: 15px; padding: 15px 0; border-bottom: 1px solid var(--line); }
    .news-tag { width: fit-content; padding: 4px 8px; border-radius: 4px; color: var(--blue); background: var(--soft-blue); font-size: 11px; font-weight: 750; }
    .news-list a { font-size: 14px; font-weight: 650; }
    .news-list a:hover { color: var(--blue); }
    .news-list time { color: #8492a0; font-size: 12px; white-space: nowrap; }
    .quote-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 15px; }
    .quote {
      padding: 22px; border-left: 3px solid var(--teal); border-radius: 0 6px 6px 0;
      background: #fff; box-shadow: 0 5px 18px rgba(27,54,81,.04);
    }
    .quote p { margin: 0 0 14px; color: #46596b; font-size: 14px; }
    .quote cite { color: #7b8997; font-size: 12px; font-style: normal; }
    .share-band { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding: 25px 28px; border: 1px solid #d8e7f1; border-radius: var(--radius); background: #eef7fc; }
    .share-band h2 { margin: 0 0 5px; font-size: 20px; }
    .share-band p { margin: 0; color: var(--muted); font-size: 14px; }
    .share-actions { display: flex; gap: 9px; flex: 0 0 auto; }
    .share-actions button { min-height: 40px; padding: 0 13px; border: 1px solid #c8dbe9; border-radius: 5px; color: #36536d; background: #fff; cursor: pointer; transition: background .2s ease, border-color .2s ease; }
    .share-actions button:hover { border-color: var(--blue); color: var(--blue); background: #f9fdff; }
    .faq-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; }
    .faq-item { padding: 20px; border: 1px solid var(--line); border-radius: 6px; background: #fff; }
    .faq-item h3 { margin: 0 0 8px; font-size: 16px; }
    .faq-item p { margin: 0; color: var(--muted); font-size: 14px; }
    .closing {
      padding: 48px 0; color: #fff; background: #174f79;
    }
    .closing-inner { display: flex; align-items: center; justify-content: space-between; gap: 24px; }
    .closing h2 { margin: 0 0 6px; font-size: 25px; }
    .closing p { margin: 0; color: #d5e8f6; }
    .closing .button { color: #174f79; background: #fff; }
    .closing .button:hover { background: #e9f5fc; }
    .site-footer { padding: 45px 0 20px; color: #d3deea; background: #152b3d; }
    .footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 35px; padding-bottom: 32px; }
    .footer-brand .brand { color: #fff; }
    .footer-brand p { max-width: 320px; margin: 14px 0 0; color: #aebdca; font-size: 13px; }
    .footer-col h3 { margin: 3px 0 13px; color: #fff; font-size: 14px; }
    .footer-col ul { display: grid; gap: 8px; margin: 0; padding: 0; list-style: none; }
    .footer-col a { color: #b6c5d2; font-size: 13px; transition: color .2s ease; }
    .footer-col a:hover { color: #fff; }
    .copyright { display: flex; justify-content: space-between; gap: 16px; padding-top: 17px; border-top: 1px solid rgba(255,255,255,.13); color: #91a3b2; font-size: 12px; }
    .copyright a { color: #aebdca; }
    .notice { color: #9baebd; }
    .toast {
      position: fixed; right: 22px; bottom: 22px; z-index: 40; padding: 11px 16px;
      border-radius: 6px; color: #fff; background: #173d58; box-shadow: var(--shadow);
      opacity: 0; transform: translateY(10px); pointer-events: none; transition: .2s ease;
    }
    .toast.show { opacity: 1; transform: translateY(0); }
    @media (max-width: 1024px) {
      .nav-links { gap: 16px; }
      .topic-grid { grid-template-columns: repeat(2, 1fr); }
      .collection-layout { grid-template-columns: 1fr 1fr; }
      .footer-grid { grid-template-columns: 1.3fr 1fr 1fr; }
      .footer-col:last-child { grid-column: 2 / 4; }
    }
    @media (max-width: 768px) {
      .container { width: min(100% - 36px, var(--container)); }
      .nav-wrap { min-height: 68px; }
      .brand-name { max-width: 230px; font-size: 14px; }
      .menu-toggle { display: grid; place-items: center; flex: 0 0 auto; }
      .nav-links {
        display: none; position: absolute; top: calc(100% + 1px); left: 0; right: 0;
        padding: 10px 18px 17px; border-bottom: 1px solid var(--line); background: #fff;
        box-shadow: 0 14px 20px rgba(27,54,81,.08);
      }
      .nav-links.open { display: grid; gap: 3px; }
      .nav-links a { width: 100%; padding: 0 10px; }
      .nav-links .nav-cta { width: fit-content; margin-top: 5px; }
      .hero { padding: 54px 0 46px; }
      .hero::after { right: -240px; }
      .section { padding: 50px 0; }
      .section-head { align-items: flex-start; flex-direction: column; gap: 10px; }
      .section-head h2 { font-size: 25px; }
      .collection-layout, .split-content, .news-layout { grid-template-columns: 1fr; gap: 22px; }
      .feature-panel { min-height: 260px; }
      .check-list { grid-template-columns: 1fr 1fr; }
      .steps { grid-template-columns: 1fr; }
      .step + .step { border-left: 0; border-top: 1px solid var(--line); }
      .news-intro { padding-right: 0; }
      .signal-row { gap: 12px; }
      .signal { padding: 17px 0; }
      .quote-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .footer-brand { grid-column: 1 / -1; }
      .footer-col:last-child { grid-column: auto; }
    }
    @media (max-width: 520px) {
      .container { width: calc(100% - 30px); }
      .brand-mark { width: 34px; height: 34px; }
      .brand-name { max-width: 220px; font-size: 13px; }
      h1 { font-size: 34px; }
      .hero-subtitle { font-size: 18px; }
      .hero-copy { font-size: 14px; }
      .hero-form { align-items: stretch; flex-direction: column; }
      .hero-form input { height: 42px; }
      .hero-form .button { width: 100%; }
      .topic-grid, .directory, .check-list, .faq-list { grid-template-columns: 1fr; }
      .topic-card { min-height: auto; }
      .feature-panel { min-height: 275px; padding: 23px; }
      .feature-panel h3 { font-size: 25px; }
      .signal-row { grid-template-columns: 1fr; gap: 4px; }
      .news-list li { grid-template-columns: 76px 1fr; gap: 8px 12px; }
      .news-list time { grid-column: 2; }
      .share-band, .closing-inner { align-items: flex-start; flex-direction: column; }
      .share-actions { width: 100%; }
      .share-actions button { flex: 1; }
      .footer-grid { grid-template-columns: 1fr 1fr; gap: 25px 16px; }
      .footer-brand { grid-column: 1 / -1; }
      .copyright { flex-direction: column; gap: 5px; }
      .compare th, .compare td { padding: 12px; }
    }
    @media (prefers-reduced-motion: reduce) {
      *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; }
    }