/* roulang page: index */
:root {
      --primary: #2E74A6;
      --primary-dark: #1E557A;
      --primary-soft: #E7F1F7;
      --accent: #3C8F7A;
      --accent-soft: #E7F4EF;
      --bg: #F4F7F9;
      --surface: #FFFFFF;
      --line: #E3EAEF;
      --ink: #16313C;
      --text: #1B2A32;
      --muted: #5C6C74;
      --danger: #C4574A;
      --danger-soft: #F8E8E6;
      --radius-card: 14px;
      --radius-btn: 8px;
      --radius-input: 8px;
      --radius-badge: 999px;
      --shadow: 0 10px 28px rgba(30, 74, 110, 0.08), 0 1px 0 rgba(255, 255, 255, 0.8);
      --shadow-hover: 0 16px 40px rgba(30, 74, 110, 0.14);
      --container: 1240px;
      --header-h: 108px;
      --bar-h: 64px;
      --space-section: 108px;
      --font: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Heiti SC", sans-serif;
    }
    *, *::before, *::after { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      font-family: var(--font);
      font-size: 16px;
      line-height: 1.75;
      color: var(--text);
      background: var(--bg);
      padding-bottom: calc(var(--bar-h) + 18px);
      overflow-x: hidden;
    }
    img { max-width: 100%; height: auto; display: block; }
    a { color: var(--primary-dark); text-decoration: none; }
    a:hover { color: var(--primary); }
    button, input, select, textarea { font-family: inherit; font-size: 16px; }
    button { cursor: pointer; }
    h1, h2, h3, h4, p { margin: 0; }
    ul, ol { margin: 0; padding: 0; list-style: none; }
    table { border-collapse: collapse; width: 100%; }
    .container { width: min(100% - 40px, var(--container)); margin: 0 auto; }
    .skip {
      position: absolute; left: -999px; top: 0;
    }
    .skip:focus { left: 12px; top: 12px; background: #fff; padding: 8px 12px; z-index: 80; }
    .site-header {
      position: sticky; top: 0; z-index: 40;
      background: rgba(244, 247, 249, 0.94);
      backdrop-filter: blur(8px);
      border-bottom: 1px solid transparent;
      transition: box-shadow .25s ease, border-color .25s ease;
    }
    .site-header.is-scrolled {
      box-shadow: 0 8px 24px rgba(22, 49, 60, 0.08);
      border-bottom-color: var(--line);
    }
    .topbar {
      height: 36px;
      background: var(--primary-soft);
      color: var(--primary-dark);
      font-size: 13px;
      display: flex;
      align-items: center;
    }
    .topbar-inner, .nav-inner {
      display: flex; align-items: center; justify-content: space-between; gap: 16px;
    }
    .topbar a { color: var(--primary-dark); }
    .topbar a:hover { color: var(--primary); }
    .topbar-left, .topbar-right, .nav-links { display: flex; align-items: center; gap: 18px; flex-wrap: wrap; }
    .topbar-dot { width: 4px; height: 4px; border-radius: 50%; background: var(--accent); display: inline-block; }
    .nav-row { min-height: 72px; display: flex; align-items: center; }
    .brand {
      display: flex; align-items: center; gap: 10px; color: var(--ink); min-height: 44px;
    }
    .brand-mark {
      width: 36px; height: 36px; border-radius: 10px;
      background: linear-gradient(180deg, #3B8BB8 0%, var(--primary-dark) 100%);
      display: grid; place-items: center; box-shadow: inset 0 1px 0 rgba(255,255,255,.35);
      flex: 0 0 36px;
    }
    .brand-name { font-size: 18px; font-weight: 700; letter-spacing: 0.02em; line-height: 1.2; }
    .brand-sub { display: block; font-size: 11px; color: var(--muted); font-weight: 500; margin-top: 2px; }
    .nav-links a {
      color: var(--text); font-size: 15px; font-weight: 500; padding: 10px 2px;
      border-bottom: 2px solid transparent; min-height: 44px; display: inline-flex; align-items: center;
    }
    .nav-links a:hover, .nav-links a.is-active { color: var(--primary); border-bottom-color: var(--primary); }
    .nav-cta { margin-left: 8px; }
    .menu-toggle {
      display: none; width: 44px; height: 44px; border: 1px solid var(--line); border-radius: var(--radius-btn);
      background: var(--surface); align-items: center; justify-content: center; flex-direction: column; gap: 5px;
    }
    .menu-toggle span { width: 18px; height: 2px; background: var(--ink); display: block; }
    .btn {
      display: inline-flex; align-items: center; justify-content: center; gap: 8px;
      min-height: 44px; padding: 0 18px; border-radius: var(--radius-btn);
      border: 1px solid transparent; font-weight: 600; line-height: 1.2; transition: .2s ease;
    }
    .btn-primary { background: var(--primary); color: #fff; }
    .btn-primary:hover, .btn-primary:active { background: var(--primary-dark); transform: translateY(-1px); color: #fff; }
    .btn-ghost { background: transparent; color: #fff; border-color: rgba(255,255,255,.7); }
    .btn-ghost:hover { background: rgba(255,255,255,.12); color: #fff; }
    .btn-line { background: #fff; color: var(--primary-dark); border-color: var(--primary); }
    .btn-line:hover { background: var(--primary-soft); color: var(--primary-dark); transform: translateY(-1px); }
    .btn:focus-visible, a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible {
      outline: 2px solid var(--primary); outline-offset: 2px;
    }
    .btn-block { width: 100%; }
    .badge {
      display: inline-flex; align-items: center; gap: 6px; padding: 4px 10px;
      border-radius: var(--radius-badge); font-size: 12px; font-weight: 600; background: var(--primary-soft); color: var(--primary-dark);
    }
    .badge-accent { background: var(--accent-soft); color: #246857; }
    .badge-hot { background: #F3E7D8; color: #8A5A22; }
    section { position: relative; }
    .section { padding: var(--space-section) 0; }
    .section-alt { background: var(--surface); }
    .section-head { margin-bottom: 36px; max-width: 760px; }
    .section-head h2 { font-size: 32px; line-height: 1.3; font-weight: 700; color: var(--ink); margin-bottom: 14px; }
    .section-head p { color: var(--muted); }
    .kicker { color: var(--primary); font-size: 13px; font-weight: 700; letter-spacing: .08em; margin-bottom: 8px; }
    .hero {
      min-height: 100vh; position: relative; color: #fff; overflow: hidden; background: var(--ink);
    }
    .hero-slide {
      position: absolute; inset: 0; opacity: 0; transition: opacity .5s ease; pointer-events: none;
    }
    .hero-slide.is-active { opacity: 1; pointer-events: auto; }
    .hero-slide img {
      width: 100%; height: 100%; object-fit: cover; filter: saturate(.86) hue-rotate(8deg) contrast(1.05);
    }
    .hero-slide::after {
      content: ""; position: absolute; inset: 0;
      background: linear-gradient(90deg, rgba(22,49,60,.78) 0%, rgba(22,49,60,.48) 48%, rgba(22,49,60,.28) 100%);
    }
    .hero-copy {
      position: relative; z-index: 2; min-height: 100vh; display: grid;
      grid-template-columns: minmax(0, 1.15fr) minmax(280px, .7fr); gap: 40px; align-items: center;
      padding: calc(var(--header-h) + 28px) 0 88px;
    }
    .hero h1, .slide-title {
      font-size: 40px; line-height: 1.22; font-weight: 750; max-width: 16em; margin-bottom: 18px;
    }
    .hero-lead { font-size: 17px; line-height: 1.8; max-width: 38em; color: rgba(255,255,255,.9); margin-bottom: 22px; }
    .hero-trust { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 28px; }
    .hero-trust span {
      border: 1px solid rgba(255,255,255,.28); background: rgba(22,49,60,.28);
      color: #fff; border-radius: var(--radius-badge); padding: 6px 12px; font-size: 12px;
    }
    .hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
    .grade-panel {
      background: rgba(255,255,255,.1); border: 1px solid rgba(255,255,255,.18);
      border-radius: var(--radius-card); padding: 22px; backdrop-filter: blur(6px);
    }
    .grade-panel h3 { font-size: 16px; margin-bottom: 14px; }
    .grade-item {
      display: grid; grid-template-columns: 42px 1fr; gap: 12px; align-items: center;
      padding: 10px 0; border-top: 1px solid rgba(255,255,255,.12);
    }
    .grade-item:first-of-type { border-top: 0; }
    .grade-tag {
      width: 42px; height: 42px; border-radius: 10px; display: grid; place-items: center;
      background: #fff; color: var(--primary-dark); font-weight: 800;
    }
    .grade-item strong { display: block; font-size: 14px; }
    .grade-item span { display: block; font-size: 12px; color: rgba(255,255,255,.78); }
    .hero-nav, .hero-dots {
      position: absolute; z-index: 3;
    }
    .hero-nav { top: 50%; transform: translateY(-50%); width: 44px; height: 44px; border-radius: 8px; border: 1px solid rgba(255,255,255,.4); background: rgba(22,49,60,.35); color: #fff; }
    .hero-nav.prev { left: 18px; }
    .hero-nav.next { right: 18px; }
    .hero-nav:hover { background: var(--primary); }
    .hero-dots { left: 50%; bottom: 28px; transform: translateX(-50%); display: flex; gap: 8px; }
    .hero-dots button {
      width: 10px; height: 10px; border-radius: 50%; border: 0; background: rgba(255,255,255,.4); padding: 0; min-height: 10px;
    }
    .hero-dots button.is-active { background: #fff; width: 22px; border-radius: 999px; }
    .metrics { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: -56px; position: relative; z-index: 4; }
    .metric {
      background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius-card);
      box-shadow: var(--shadow); padding: 28px 26px; display: grid; grid-template-columns: 52px 1fr; gap: 16px; align-items: center;
    }
    .metric:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
    .metric-ico {
      width: 52px; height: 52px; border-radius: 12px; background: var(--primary-soft); color: var(--primary-dark);
      display: grid; place-items: center;
    }
    .metric b { font-variant-numeric: tabular-nums; font-size: 30px; line-height: 1.1; color: var(--ink); display: block; }
    .metric strong { display: block; margin: 6px 0 4px; }
    .metric p { color: var(--muted); font-size: 14px; }
    .split { display: grid; grid-template-columns: 1.05fr .95fr; gap: 48px; align-items: center; }
    .param-table { width: 100%; margin-top: 22px; border: 1px solid var(--line); border-radius: 12px; overflow: hidden; background: #fff; }
    .param-table th, .param-table td { text-align: left; padding: 12px 16px; border-bottom: 1px solid var(--line); font-size: 14px; }
    .param-table th { width: 34%; background: var(--primary-soft); color: var(--primary-dark); font-weight: 650; }
    .param-table tr:last-child th, .param-table tr:last-child td { border-bottom: 0; }
    .check-list { margin-top: 18px; display: grid; gap: 8px; }
    .check-list li { padding-left: 26px; position: relative; color: var(--muted); }
    .check-list li::before { content: ""; position: absolute; left: 0; top: 10px; width: 14px; height: 14px; border-radius: 50%; background: var(--accent); box-shadow: inset 0 0 0 3px var(--accent-soft); }
    .media-frame {
      border-radius: var(--radius-card); overflow: hidden; box-shadow: var(--shadow); position: relative;
    }
    .media-frame img { width: 100%; height: 460px; object-fit: cover; filter: saturate(.9) hue-rotate(6deg); }
    .media-caption {
      position: absolute; left: 16px; bottom: 16px; background: rgba(22,49,60,.78); color: #fff;
      padding: 8px 12px; border-radius: 8px; font-size: 13px;
    }
    .scene-track {
      display: grid; grid-auto-flow: column; grid-auto-columns: minmax(320px, 1fr);
      gap: 18px; overflow-x: auto; scroll-snap-type: x mandatory; padding-bottom: 10px;
    }
    .scene-card {
      scroll-snap-align: start; background: #fff; border-radius: var(--radius-card); overflow: hidden;
      border: 1px solid var(--line); box-shadow: var(--shadow); min-height: 100%;
    }
    .scene-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
    .scene-card img { height: 190px; width: 100%; object-fit: cover; filter: saturate(.88) hue-rotate(8deg); }
    .scene-body { padding: 20px 20px 22px; }
    .scene-body h3 { font-size: 18px; margin: 8px 0; }
    .scene-body p { color: var(--muted); font-size: 14px; }
    .mod-line { margin-top: 12px; padding-top: 12px; border-top: 1px solid var(--line); font-size: 13px; color: var(--primary-dark); font-weight: 650; }
    .adv-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; align-items: stretch; }
    .adv-card {
      background: #fff; border: 1px solid var(--line); border-radius: var(--radius-card); box-shadow: var(--shadow);
      padding: 22px; display: flex; flex-direction: column; gap: 10px;
    }
    .adv-card:nth-child(2), .adv-card:nth-child(5) { margin-top: 18px; }
    .adv-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
    .adv-card h3 { font-size: 18px; }
    .adv-card p { color: var(--muted); font-size: 14px; flex: 1; }
    .adv-spec { border-top: 1px dashed var(--line); padding-top: 10px; font-size: 13px; color: var(--primary-dark); }
    .product-grid {
      display: grid; grid-template-columns: 1.35fr 1fr; grid-template-rows: auto auto; gap: 20px;
    }
    .product-card {
      background: #fff; border: 1px solid var(--line); border-radius: var(--radius-card); box-shadow: var(--shadow); overflow: hidden;
      display: flex; flex-direction: column;
    }
    .product-card.featured { grid-row: 1 / span 2; }
    .product-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
    .product-card img { width: 100%; height: 220px; object-fit: cover; filter: saturate(.9) hue-rotate(6deg); }
    .product-card.featured img { height: 340px; }
    .product-body { padding: 22px; display: flex; flex-direction: column; gap: 10px; flex: 1; }
    .product-body h3 { font-size: 20px; }
    .spec-bar { display: flex; flex-wrap: wrap; gap: 8px; }
    .spec-bar span { background: var(--bg); border: 1px solid var(--line); border-radius: 8px; padding: 6px 10px; font-size: 12px; color: var(--muted); }
    .cases {
      background: var(--ink); color: #fff; padding: 88px 0;
    }
    .cases-box {
      display: grid; grid-template-columns: 1.1fr .9fr; gap: 36px; align-items: center;
      border: 1px solid rgba(255,255,255,.12); clip-path: polygon(18px 0, 100% 0, 100% calc(100% - 18px), calc(100% - 18px) 100%, 0 100%, 0 18px);
      overflow: hidden; background: #122830;
    }
    .cases-box img { width: 100%; height: 100%; min-height: 420px; object-fit: cover; filter: saturate(.8); }
    .cases-photo { position: relative; }
    .cases-photo::after { content: ""; position: absolute; inset: 0; background: rgba(22,49,60,.42); }
    .cases-copy { padding: 36px 36px 36px 8px; }
    .cases-copy h2 { font-size: 30px; margin: 8px 0 16px; }
    .result { display: grid; gap: 14px; margin-top: 8px; }
    .result li { background: rgba(255,255,255,.06); border-left: 3px solid var(--accent); padding: 12px 14px; }
    .result b { font-variant-numeric: tabular-nums; display: block; font-size: 22px; }
    .story { display: grid; grid-template-columns: .9fr 1.1fr; gap: 36px; align-items: center; margin-bottom: 48px; }
    .story.reverse { grid-template-columns: 1.1fr .9fr; }
    .story.reverse .story-media { order: 2; }
    .story img { width: 100%; height: 340px; object-fit: cover; border-radius: var(--radius-card); box-shadow: var(--shadow); filter: saturate(.9) hue-rotate(6deg); }
    .quote { color: var(--muted); margin: 12px 0 18px; }
    .who { font-size: 14px; color: var(--primary-dark); font-weight: 650; }
    .compare-wrap { overflow-x: auto; }
    .compare-table { min-width: 720px; background: #fff; border-radius: var(--radius-card); box-shadow: var(--shadow); overflow: hidden; }
    .compare-table th, .compare-table td { padding: 16px 18px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
    .compare-table thead th { background: var(--bg); font-size: 14px; }
    .compare-table thead th.hi { background: var(--primary); color: #fff; }
    .compare-table td.hi { background: var(--primary-soft); color: var(--ink); font-weight: 650; }
    .ok { color: var(--accent); font-weight: 800; margin-right: 6px; }
    .compare-cards { display: none; }
    .stats-band {
      display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px;
      background: var(--primary-soft); border-radius: 18px; padding: 36px 24px;
    }
    .stat { text-align: center; }
    .stat b { font-variant-numeric: tabular-nums; font-size: 36px; color: var(--primary-dark); display: block; line-height: 1.1; }
    .stat span { color: var(--muted); font-size: 14px; }
    .review-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
    .review {
      background: #fff; border: 1px solid var(--line); border-radius: var(--radius-card); box-shadow: var(--shadow); padding: 20px;
    }
    .review:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
    .review-hd { display: flex; gap: 12px; align-items: center; margin-bottom: 10px; }
    .review-hd img { width: 48px; height: 48px; border-radius: 50%; object-fit: cover; }
    .stars { color: #C9A227; letter-spacing: 1px; font-size: 13px; }
    .review p { color: var(--muted); font-size: 14px; }
    .news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
    .news-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius-card); box-shadow: var(--shadow); overflow: hidden; display: flex; flex-direction: column; }
    .news-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
    .news-card img { height: 180px; width: 100%; object-fit: cover; }
    .news-card .body { padding: 18px 18px 20px; }
    .news-card time { color: var(--muted); font-size: 13px; }
    .news-card h3 { font-size: 18px; margin: 8px 0; }
    .news-card p { color: var(--muted); font-size: 14px; }
    .more-link { display: inline-flex; min-height: 44px; align-items: center; margin-top: 22px; font-weight: 700; color: var(--primary-dark); }
    .steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; position: relative; }
    .steps::before {
      content: ""; position: absolute; top: 28px; left: 8%; right: 8%; height: 2px; background: var(--line);
    }
    .step {
      background: #fff; border: 1px solid var(--line); border-radius: var(--radius-card); box-shadow: var(--shadow); padding: 22px; position: relative;
    }
    .step b {
      width: 36px; height: 36px; border-radius: 50%; background: var(--primary); color: #fff; display: grid; place-items: center; margin-bottom: 12px;
    }
    .step h3 { font-size: 18px; margin-bottom: 8px; }
    .step p { color: var(--muted); font-size: 14px; }
    .faq-list { display: grid; gap: 12px; }
    .faq-item { background: #fff; border: 1px solid var(--line); border-radius: 12px; overflow: hidden; }
    .faq-item.is-open { border-left: 3px solid var(--primary); }
    .faq-item button {
      width: 100%; text-align: left; background: #fff; border: 0; padding: 16px 48px 16px 18px;
      min-height: 56px; font-weight: 700; color: var(--ink); position: relative;
    }
    .faq-item button::after { content: "+"; position: absolute; right: 18px; top: 50%; transform: translateY(-50%); color: var(--primary); font-size: 20px; }
    .faq-item.is-open button::after { content: "–"; }
    .faq-item .ans { display: none; padding: 0 18px 16px; color: var(--muted); }
    .faq-item.is-open .ans { display: block; }
    .guarantee {
      display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px;
      background: var(--primary-soft); border-radius: 16px; padding: 22px;
    }
    .g-item { display: grid; grid-template-columns: 42px 1fr; gap: 10px; align-items: center; min-height: 64px; }
    .g-item span {
      width: 42px; height: 42px; border-radius: 10px; background: #fff; color: var(--primary-dark); display: grid; place-items: center; font-weight: 800;
    }
    .g-item strong { display: block; font-size: 15px; }
    .g-item em { font-style: normal; color: var(--muted); font-size: 13px; }
    .contact-grid { display: grid; grid-template-columns: .85fr 1.15fr; gap: 36px; align-items: start; }
    .contact-side { background: var(--ink); color: #fff; border-radius: var(--radius-card); padding: 36px; min-height: 100%; }
    .contact-side h2 { font-size: 30px; margin-bottom: 14px; }
    .contact-side p { color: rgba(255,255,255,.82); margin-bottom: 22px; }
    .contact-side li { margin-bottom: 10px; }
    .form {
      background: #fff; border: 1px solid var(--line); border-radius: var(--radius-card); box-shadow: var(--shadow); padding: 28px;
    }
    .form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
    .field { display: flex; flex-direction: column; gap: 6px; }
    .field.full { grid-column: 1 / -1; }
    .field label { font-weight: 650; font-size: 14px; }
    .req { color: var(--danger); }
    .field input, .field select, .field textarea {
      min-height: 44px; border: 1px solid var(--line); border-radius: var(--radius-input);
      padding: 10px 12px; background: var(--bg); color: var(--text);
    }
    .field textarea { min-height: 110px; resize: vertical; }
    .field.is-error input, .field.is-error select, .field.is-error textarea { border-color: var(--danger); background: var(--danger-soft); }
    .err { display: none; color: var(--danger); font-size: 13px; }
    .field.is-error .err { display: block; }
    .form-note { color: var(--muted); font-size: 13px; margin-top: 10px; }
    .form-ok { display: none; background: var(--accent-soft); color: #246857; padding: 12px 14px; border-radius: 8px; margin-bottom: 12px; }
    .site-footer { background: #12262E; color: rgba(255,255,255,.82); padding: 56px 0 28px; }
    .footer-grid { display: grid; grid-template-columns: 1.2fr .9fr 1fr; gap: 32px; margin-bottom: 28px; }
    .site-footer h3 { color: #fff; font-size: 16px; margin-bottom: 12px; }
    .site-footer a { color: rgba(255,255,255,.82); display: inline-flex; min-height: 36px; align-items: center; }
    .site-footer a:hover { color: #fff; }
    .copy { border-top: 1px solid rgba(255,255,255,.1); padding-top: 16px; font-size: 13px; color: rgba(255,255,255,.6); }
    .dock {
      position: fixed; left: 0; right: 0; bottom: 0; z-index: 30;
      background: var(--ink); color: #fff; min-height: var(--bar-h);
      display: flex; align-items: center; box-shadow: 0 -8px 24px rgba(22,49,60,.2);
    }
    .dock-inner { display: flex; align-items: center; justify-content: space-between; gap: 12px; width: min(100% - 24px, var(--container)); margin: 0 auto; }
    .dock p { font-size: 14px; }
    .dock-close {
      width: 44px; height: 44px; border: 0; background: transparent; color: #fff; font-size: 20px;
    }
    .drawer {
      position: fixed; inset: 0; background: rgba(22,49,60,.46); z-index: 50; display: none;
    }
    .drawer.is-open { display: block; }
    .drawer-panel {
      position: absolute; right: 0; top: 0; bottom: 0; width: min(86vw, 360px); background: #fff;
      padding: 24px 20px 28px; display: flex; flex-direction: column; gap: 8px;
    }
    .drawer-panel a { min-height: 44px; display: flex; align-items: center; color: var(--text); font-weight: 650; border-bottom: 1px solid var(--line); }
    .drawer-close { align-self: flex-end; width: 44px; height: 44px; border: 1px solid var(--line); border-radius: 8px; background: #fff; }
    .dots-bg {
      background-image: radial-gradient(rgba(30,74,110,.06) 1px, transparent 1px);
      background-size: 18px 18px;
    }
    .ring {
      position: absolute; width: 240px; height: 240px; border: 1px solid rgba(46,116,166,.12); border-radius: 50%;
      right: -40px; top: -40px; pointer-events: none;
    }
    @media (max-width: 1280px) {
      .hero h1, .slide-title { font-size: 36px; }
      .section-head h2 { font-size: 28px; }
    }
    @media (max-width: 1024px) {
      :root { --space-section: 84px; }
      .nav-links { display: none; }
      .nav-cta { display: none; }
      .menu-toggle { display: inline-flex; }
      .hero-copy { grid-template-columns: 1fr; padding-bottom: 96px; }
      .grade-panel { max-width: 420px; }
      .metrics, .adv-grid, .stats-band, .review-grid, .news-grid, .steps, .guarantee, .contact-grid, .footer-grid, .split, .cases-box, .story, .story.reverse, .product-grid {
        grid-template-columns: 1fr 1fr;
      }
      .product-card.featured { grid-row: auto; }
      .product-card.featured img { height: 240px; }
      .story.reverse .story-media { order: 0; }
      .steps::before { display: none; }
      .adv-card:nth-child(2), .adv-card:nth-child(5) { margin-top: 0; }
      .cases-copy { padding: 24px; }
      .review-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      :root { --space-section: 64px; --header-h: 92px; }
      .topbar-right { display: none; }
      .hero { min-height: 640px; }
      .hero-copy { min-height: 640px; padding-top: 118px; }
      .hero h1, .slide-title { font-size: 30px; }
      .hero-lead { font-size: 16px; }
      .hero-actions .btn { flex: 1 1 100%; }
      .metrics, .adv-grid, .stats-band, .review-grid, .news-grid, .steps, .guarantee, .contact-grid, .footer-grid, .split, .cases-box, .story, .product-grid {
        grid-template-columns: 1fr;
      }
      .metric { grid-template-columns: 48px 1fr; }
      .media-frame img, .story img, .cases-box img { height: 240px; min-height: 240px; }
      .form-grid { grid-template-columns: 1fr; }
      .compare-table { display: none; }
      .compare-cards { display: grid; gap: 12px; }
      .cmp-card { background: #fff; border: 1px solid var(--line); border-radius: 12px; box-shadow: var(--shadow); padding: 16px; }
      .cmp-card h3 { margin-bottom: 8px; }
      .cmp-old { color: var(--muted); font-size: 14px; }
      .cmp-new { margin-top: 6px; background: var(--primary-soft); padding: 8px 10px; border-radius: 8px; font-weight: 650; }
      .dock-inner { flex-wrap: wrap; padding: 8px 0; }
      .dock p { font-size: 13px; }
      .brand-name { font-size: 16px; }
      .scene-track { grid-auto-columns: minmax(78vw, 1fr); }
    }
    @media (max-width: 375px) {
      .container { width: min(100% - 24px, var(--container)); }
      .hero h1, .slide-title { font-size: 26px; }
      .section-head h2, .contact-side h2 { font-size: 24px; }
      .stat b { font-size: 28px; }
      .hero-nav { display: none; }
    }

/* roulang page: index */
:root{
  --primary:#2E74A6;
  --primary-dark:#1E557A;
  --primary-soft:#E7F1F7;
  --accent:#3C8F7A;
  --accent-soft:#E7F4EF;
  --bg:#F4F7F9;
  --surface:#FFFFFF;
  --line:#E3EAEF;
  --ink:#16313C;
  --text:#1B2A32;
  --muted:#5C6C74;
  --danger:#B42318;
  --danger-soft:#FDECEC;
  --radius-card:14px;
  --radius-btn:8px;
  --radius-input:8px;
  --radius-pill:999px;
  --shadow:0 10px 28px rgba(30,74,110,0.08),0 1px 0 rgba(255,255,255,0.8);
  --shadow-hover:0 16px 40px rgba(30,74,110,0.14);
  --header-top:36px;
  --header-main:72px;
  --container:1240px;
  --space-section:108px;
  --focus:2px solid #2E74A6;
}
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth;scroll-padding-top:124px}
body{
  font-family:"Noto Sans SC","PingFang SC","Microsoft YaHei","Hiragino Sans GB",sans-serif;
  font-size:16px;line-height:1.75;color:var(--text);background:var(--bg);
  overflow-x:hidden;padding-bottom:78px;
}
img{max-width:100%;display:block;height:auto}
a{color:var(--primary);text-decoration:none;transition:color .2s ease,opacity .2s ease}
a:hover{color:var(--primary-dark)}
button,input,select,textarea{font-family:inherit;font-size:inherit}
button{cursor:pointer;border:none;background:none}
ul,ol{list-style:none}
.container{width:min(100% - 40px,var(--container));margin:0 auto}
.skip{position:absolute;left:-999px;top:8px;background:#fff;padding:8px 12px;z-index:100}
.skip:focus{left:8px}
:focus-visible{outline:var(--focus);outline-offset:2px}
.num{font-variant-numeric:tabular-nums;font-feature-settings:"tnum"}
.badge{
  display:inline-flex;align-items:center;gap:6px;height:28px;padding:0 12px;
  border-radius:var(--radius-pill);font-size:12px;font-weight:600;letter-spacing:.02em;
  background:var(--primary-soft);color:var(--primary-dark);
}
.badge.accent{background:var(--accent-soft);color:#246857}
.badge.ink{background:rgba(255,255,255,.12);color:#fff}
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  min-height:44px;padding:0 20px;border-radius:var(--radius-btn);font-weight:600;
  line-height:1;border:1px solid transparent;transition:transform .2s ease,background .2s ease,box-shadow .2s ease,border-color .2s ease;
}
.btn:hover{transform:translateY(-2px)}
.btn:active{transform:translateY(0)}
.btn-primary{background:var(--primary);color:#fff;box-shadow:0 8px 18px rgba(46,116,166,.22)}
.btn-primary:hover{background:#286890;color:#fff}
.btn-ghost{background:transparent;color:#fff;border-color:rgba(255,255,255,.7)}
.btn-ghost:hover{background:rgba(255,255,255,.12);color:#fff}
.btn-line{background:#fff;color:var(--primary);border-color:var(--primary)}
.btn-line:hover{background:var(--primary-soft);color:var(--primary-dark)}
.section{padding:var(--space-section) 0;position:relative}
.section-head{margin-bottom:36px;max-width:760px}
.section-head h2{font-size:32px;line-height:1.3;font-weight:700;letter-spacing:.01em;margin-bottom:12px}
.section-head p{color:var(--muted)}
.kicker{font-size:13px;font-weight:600;color:var(--primary);margin-bottom:8px;letter-spacing:.08em}
.card{
  background:var(--surface);border:1px solid var(--line);border-radius:var(--radius-card);
  box-shadow:var(--shadow);transition:transform .22s ease,box-shadow .22s ease;
}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-hover)}
.site-header{position:sticky;top:0;z-index:80;background:#fff;border-bottom:1px solid transparent;transition:box-shadow .2s ease,border-color .2s ease}
.site-header.is-scrolled{box-shadow:0 8px 24px rgba(22,49,60,.08);border-bottom-color:var(--line)}
.topbar{
  height:var(--header-top);background:var(--primary-soft);color:var(--primary-dark);
  font-size:12px;display:flex;align-items:center;
}
.topbar .container{display:flex;align-items:center;justify-content:space-between;gap:16px}
.topbar a{color:var(--primary-dark)}
.topbar a:hover{color:var(--primary)}
.topbar-left,.topbar-right{display:flex;align-items:center;gap:18px}
.nav-main{height:var(--header-main);display:flex;align-items:center}
.nav-main .container{display:flex;align-items:center;gap:24px}
.logo{display:flex;align-items:center;gap:10px;color:var(--ink);font-weight:700;font-size:18px;flex-shrink:0}
.logo-mark{
  width:36px;height:36px;border-radius:10px;background:linear-gradient(180deg,#3B8FBE,#2E74A6);
  display:grid;place-items:center;box-shadow:inset 0 1px 0 rgba(255,255,255,.35);
}
.nav-links{display:flex;align-items:center;justify-content:center;gap:4px;flex:1}
.nav-links a{
  position:relative;color:var(--text);font-size:15px;font-weight:500;padding:10px 12px;min-height:44px;
  display:inline-flex;align-items:center;
}
.nav-links a::after{
  content:"";position:absolute;left:12px;right:12px;bottom:6px;height:2px;background:var(--primary);
  transform:scaleX(0);transform-origin:left;transition:transform .2s ease;
}
.nav-links a:hover,.nav-links a.is-active{color:var(--primary)}
.nav-links a.is-active::after,.nav-links a:hover::after{transform:scaleX(1)}
.nav-cta{margin-left:auto}
.menu-toggle{
  display:none;width:44px;height:44px;border-radius:8px;border:1px solid var(--line);
  align-items:center;justify-content:center;flex-direction:column;gap:5px;
}
.menu-toggle span{width:18px;height:2px;background:var(--ink);display:block;transition:transform .2s ease,opacity .2s ease}
.drawer{
  display:none;position:fixed;inset:0;background:rgba(22,49,60,.46);z-index:90;
}
.drawer.is-open{display:block}
.drawer-panel{
  position:absolute;right:0;top:0;height:100%;width:min(86vw,360px);background:#fff;
  padding:24px 20px 32px;display:flex;flex-direction:column;gap:8px;
  box-shadow:-16px 0 40px rgba(22,49,60,.16);
}
.drawer-panel a{min-height:48px;display:flex;align-items:center;padding:0 8px;color:var(--text);font-weight:600;border-bottom:1px solid var(--line)}
.drawer-close{align-self:flex-end;width:44px;height:44px;border-radius:8px;border:1px solid var(--line)}
.hero{position:relative;min-height:100vh;color:#fff;overflow:hidden;background:#16313C}
.slides{position:absolute;inset:0}
.slide{position:absolute;inset:0;opacity:0;transition:opacity .5s ease,transform .5s ease;transform:scale(1.04)}
.slide.is-active{opacity:1;transform:scale(1)}
.slide img{width:100%;height:100%;object-fit:cover;filter:saturate(.85) hue-rotate(8deg)}
.slide::after{
  content:"";position:absolute;inset:0;
  background:linear-gradient(90deg,rgba(22,49,60,.72) 0%,rgba(22,49,60,.46) 48%,rgba(22,49,60,.28) 100%);
}
.hero-copy{position:relative;z-index:2;min-height:100vh;display:flex;align-items:center;padding:132px 0 88px}
.hero-copy .container{width:min(100% - 40px,var(--container))}
.grade-row{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:18px}
.hero h1,.slide-title{font-size:42px;line-height:1.22;max-width:760px;font-weight:700;margin-bottom:16px}
.hero-lead{max-width:680px;font-size:17px;line-height:1.8;color:rgba(255,255,255,.9);margin-bottom:28px}
.hero-actions{display:flex;flex-wrap:wrap;gap:12px;margin-bottom:18px}
.hero-note{font-size:13px;color:rgba(255,255,255,.78)}
.hero-controls{position:absolute;z-index:3;left:0;right:0;bottom:28px}
.hero-controls .container{display:flex;align-items:center;justify-content:space-between;gap:12px}
.dots{display:flex;gap:8px}
.dots button{width:44px;height:44px;display:grid;place-items:center}
.dots button i{width:10px;height:10px;border-radius:50%;background:rgba(255,255,255,.4);display:block}
.dots button.is-active i{background:#fff;transform:scale(1.15)}
.arrow-group{display:flex;gap:8px}
.icon-btn{
  width:44px;height:44px;border-radius:8px;border:1px solid rgba(255,255,255,.35);
  color:#fff;display:grid;place-items:center;background:rgba(22,49,60,.28);
}
.icon-btn:hover{background:rgba(22,49,60,.5)}
.metrics{margin-top:-48px;position:relative;z-index:4;padding-bottom:24px}
.metric-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.metric{
  background:#fff;border-radius:var(--radius-card);padding:28px 26px;box-shadow:var(--shadow);border:1px solid var(--line);
  display:grid;grid-template-columns:48px 1fr;gap:16px;align-items:center;
}
.metric:hover{transform:translateY(-4px);box-shadow:var(--shadow-hover)}
.metric-ico{
  width:48px;height:48px;border-radius:12px;background:var(--primary-soft);color:var(--primary);
  display:grid;place-items:center;
}
.metric strong{display:block;font-size:30px;line-height:1.1;color:var(--ink);margin-bottom:4px}
.metric b{display:block;font-size:15px;margin-bottom:4px}
.metric span{color:var(--muted);font-size:14px}
.intro-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:48px;align-items:center}
.intro-visual{position:relative}
.intro-visual img{width:100%;height:520px;object-fit:cover;border-radius:var(--radius-card);filter:saturate(.88) hue-rotate(6deg);box-shadow:var(--shadow)}
.intro-chip{position:absolute;left:18px;bottom:18px;background:#fff;border-radius:12px;padding:12px 14px;box-shadow:var(--shadow);font-size:13px}
.spec-table{width:100%;border-collapse:collapse;margin:22px 0 18px;background:#fff;border:1px solid var(--line);border-radius:12px;overflow:hidden}
.spec-table th,.spec-table td{padding:12px 14px;text-align:left;border-bottom:1px solid var(--line);font-size:14px}
.spec-table th{width:38%;background:var(--primary-soft);color:var(--primary-dark);font-weight:600}
.check-list{display:grid;gap:8px;margin-top:8px}
.check-list li{display:flex;gap:8px;color:var(--muted);font-size:14px}
.check-list li::before{content:"";width:8px;height:8px;border-radius:50%;background:var(--accent);margin-top:9px;flex-shrink:0}
.scene-grid{display:grid;grid-template-columns:1.15fr .85fr;gap:22px}
.scene-card{position:relative;min-height:280px;border-radius:var(--radius-card);overflow:hidden;box-shadow:var(--shadow)}
.scene-card img{width:100%;height:100%;object-fit:cover;position:absolute;inset:0;filter:saturate(.82) hue-rotate(8deg)}
.scene-card::after{content:"";position:absolute;inset:0;background:linear-gradient(180deg,rgba(22,49,60,.12),rgba(22,49,60,.72))}
.scene-body{position:relative;z-index:1;padding:24px;color:#fff;height:100%;display:flex;flex-direction:column;justify-content:flex-end;min-height:280px}
.scene-card:nth-child(2){margin-top:36px}
.scene-card:nth-child(3){margin-top:-36px}
.adv-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.adv-card{padding:24px;min-height:100%}
.adv-card h3{font-size:18px;margin:10px 0 8px}
.adv-card p{color:var(--muted);font-size:14px;margin-bottom:14px}
.adv-meta{display:flex;justify-content:space-between;gap:8px;border-top:1px solid var(--line);padding-top:12px;font-size:12px;color:var(--primary-dark);font-weight:600}
.product-stage{display:grid;grid-template-columns:1.25fr .75fr;grid-template-rows:auto auto;gap:20px}
.product-card{overflow:hidden;display:flex;flex-direction:column}
.product-card.large{grid-row:span 2}
.product-card img{width:100%;height:210px;object-fit:cover;filter:saturate(.88) hue-rotate(6deg)}
.product-card.large img{height:340px}
.product-body{padding:22px}
.product-body h3{font-size:20px;margin:8px 0}
.param-bar{display:grid;grid-template-columns:1fr 1fr;gap:8px;margin:14px 0 18px}
.param-bar span{background:var(--bg);border:1px solid var(--line);border-radius:8px;padding:8px 10px;font-size:12px;color:var(--muted)}
.param-bar b{display:block;color:var(--text);font-size:13px;margin-top:2px}
.cases{background:var(--ink);color:#fff;padding:96px 0}
.cases-frame{
  display:grid;grid-template-columns:1.1fr .9fr;gap:36px;align-items:center;
  border:1px solid rgba(255,255,255,.12);padding:28px;border-radius:18px;
  clip-path:polygon(0 0,calc(100% - 28px) 0,100% 28px,100% 100%,0 100%);
  background:linear-gradient(180deg,rgba(255,255,255,.03),rgba(255,255,255,0));
}
.cases-frame img{width:100%;height:420px;object-fit:cover;border-radius:12px;filter:saturate(.75);opacity:.95}
.case-point{display:flex;gap:14px;padding:16px 0;border-bottom:1px solid rgba(255,255,255,.12)}
.case-point strong{display:block;font-size:28px}
.story{display:grid;grid-template-columns:.92fr 1.08fr;gap:40px;align-items:center;margin-bottom:56px}
.story.reverse{grid-template-columns:1.08fr .92fr}
.story.reverse .story-copy{order:-1}
.story img{width:100%;height:360px;object-fit:cover;border-radius:var(--radius-card);box-shadow:var(--shadow);filter:saturate(.88) hue-rotate(6deg)}
.quote{border-left:3px solid var(--primary);padding-left:16px;margin-top:16px;color:var(--muted)}
.compare-wrap{overflow:auto;border:1px solid var(--line);border-radius:var(--radius-card);background:#fff;box-shadow:var(--shadow)}
.compare-table{width:100%;border-collapse:collapse;min-width:680px}
.compare-table th,.compare-table td{padding:16px 18px;text-align:left;border-bottom:1px solid var(--line)}
.compare-table thead th{background:var(--bg);font-size:14px}
.compare-table thead th:last-child{background:var(--primary);color:#fff}
.compare-table td:last-child{background:var(--primary-soft);color:var(--primary-dark);font-weight:600}
.ok{color:var(--accent)}
.mobile-compare{display:none;gap:14px}
.m-card{padding:18px}
.m-card li{display:flex;justify-content:space-between;gap:12px;padding:10px 0;border-bottom:1px solid var(--line);font-size:14px}
.stats{background:linear-gradient(90deg,var(--primary-soft),#eef6f3);padding:64px 0}
.stat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
.stat{text-align:left;padding:8px 10px}
.stat strong{display:block;font-size:36px;color:var(--ink);line-height:1.1}
.stat span{color:var(--muted);font-size:14px}
.review-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:18px}
.review{padding:22px}
.review-top{display:flex;align-items:center;gap:12px;margin-bottom:12px}
.review-top img{width:48px;height:48px;border-radius:50%;object-fit:cover}
.stars{color:#D4A017;letter-spacing:2px;font-size:13px}
.news-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.news-card img{width:100%;height:190px;object-fit:cover}
.news-card .product-body{padding:18px 20px 22px}
.news-card time{font-size:12px;color:var(--muted)}
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:0;position:relative}
.steps::before{
  content:"";position:absolute;left:8%;right:8%;top:27px;height:2px;background:linear-gradient(90deg,var(--primary),var(--accent));opacity:.35
}
.step{padding:0 14px}
.step-index{
  width:54px;height:54px;border-radius:50%;background:#fff;border:2px solid var(--primary);
  display:grid;place-items:center;font-weight:700;color:var(--primary);margin-bottom:16px;position:relative;z-index:1
}
.step h3{font-size:18px;margin-bottom:8px}
.step p{color:var(--muted);font-size:14px}
.faq-list{display:grid;gap:12px}
.faq-item{background:#fff;border:1px solid var(--line);border-radius:12px;overflow:hidden}
.faq-item.is-open{border-left:3px solid var(--primary)}
.faq-q{
  width:100%;text-align:left;padding:16px 18px;min-height:56px;display:flex;align-items:center;justify-content:space-between;
  gap:12px;font-weight:600;color:var(--ink);background:#fff;
}
.faq-a{display:none;padding:0 18px 16px;color:var(--muted)}
.faq-item.is-open .faq-a{display:block}
.faq-item.is-open .faq-q{color:var(--primary-dark)}
.guarantee{background:var(--primary-soft)}
.g-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.g-item{display:flex;gap:12px;align-items:flex-start;padding:8px 4px}
.g-ico{width:44px;height:44px;border-radius:12px;background:#fff;display:grid;place-items:center;color:var(--primary);flex-shrink:0}
.contact{background:#fff}
.contact-grid{display:grid;grid-template-columns:.9fr 1.1fr;gap:40px;align-items:start}
.contact-panel{background:var(--ink);color:#fff;border-radius:var(--radius-card);padding:36px 32px;min-height:100%}
.contact-panel a{color:#fff}
.form{
  background:var(--bg);border:1px solid var(--line);border-radius:var(--radius-card);padding:28px;
  box-shadow:var(--shadow);
}
.form-row{margin-bottom:14px}
.form label{display:block;font-size:13px;font-weight:600;margin-bottom:6px}
.req{color:#B42318}
.form input,.form select,.form textarea{
  width:100%;min-height:44px;border:1px solid var(--line);border-radius:var(--radius-input);
  padding:10px 12px;background:#fff;color:var(--text);
}
.form textarea{min-height:96px;resize:vertical}
.form .is-error{border-color:var(--danger);background:var(--danger-soft)}
.form-error{display:none;color:var(--danger);font-size:12px;margin-top:4px}
.form-row.has-error .form-error{display:block}
.form-ok{display:none;background:var(--accent-soft);color:#246857;border-radius:8px;padding:10px 12px;margin-bottom:12px}
.form-tip{font-size:13px;color:var(--muted);margin-top:10px}
.site-footer{background:#10252D;color:rgba(255,255,255,.82);padding:64px 0 120px}
.footer-grid{display:grid;grid-template-columns:1.2fr .8fr 1fr;gap:32px}
.site-footer h3{color:#fff;font-size:16px;margin-bottom:14px}
.site-footer a{color:rgba(255,255,255,.82)}
.site-footer a:hover{color:#fff}
.foot-links{display:grid;gap:8px}
.copyright{margin-top:28px;padding-top:18px;border-top:1px solid rgba(255,255,255,.1);font-size:13px;color:rgba(255,255,255,.62)}
.fixed-bar{
  position:fixed;left:0;right:0;bottom:0;z-index:70;background:#fff;border-top:1px solid var(--line);
  box-shadow:0 -8px 24px rgba(22,49,60,.08);
}
.fixed-bar .container{display:flex;align-items:center;justify-content:space-between;gap:12px;min-height:64px}
.fixed-close{width:44px;height:44px;border-radius:8px;border:1px solid var(--line)}
.texture{
  background-image:radial-gradient(rgba(46,116,166,.06) 1px,transparent 1px);
  background-size:18px 18px;
}
@media (max-width:1280px){
  .hero h1,.slide-title{font-size:38px}
  .adv-grid{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:1024px){
  :root{--space-section:80px}
  .nav-links{display:none}
  .nav-cta{display:none}
  .menu-toggle{display:flex;margin-left:auto}
  .intro-grid,.cases-frame,.contact-grid,.footer-grid,.product-stage,.scene-grid{grid-template-columns:1fr}
  .story,.story.reverse{grid-template-columns:1fr}
  .story.reverse .story-copy{order:0}
  .scene-card:nth-child(2),.scene-card:nth-child(3){margin-top:0}
  .product-card.large{grid-row:auto}
  .product-card.large img,.intro-visual img,.story img,.cases-frame img{height:320px}
  .review-grid{grid-template-columns:repeat(2,1fr)}
  .steps{grid-template-columns:repeat(2,1fr);gap:24px}
  .steps::before{display:none}
  .stat-grid{grid-template-columns:repeat(2,1fr);gap:24px}
}
@media (max-width:768px){
  :root{--space-section:64px;--header-main:64px}
  .topbar-right,.topbar .hours{display:none}
  .hero{min-height:640px}
  .hero-copy{min-height:640px;padding:118px 0 92px}
  .hero h1,.slide-title{font-size:30px}
  .hero-lead{font-size:16px}
  .hero-actions{flex-direction:column}
  .hero-actions .btn{width:100%}
  .metric-grid,.g-grid,.news-grid{grid-template-columns:1fr}
  .metrics{margin-top:-28px}
  .section-head h2{font-size:26px}
  .compare-wrap{display:none}
  .mobile-compare{display:grid}
  .review-grid{grid-template-columns:1fr}
  .fixed-bar .hide-m{display:none}
  .fixed-bar .btn{flex:1}
  .site-footer{padding-bottom:140px}
}
@media (max-width:520px){
  .container{width:min(100% - 28px,var(--container))}
  .hero h1,.slide-title{font-size:26px}
  .grade-row .badge{font-size:11px}
  .metric{grid-template-columns:1fr}
  .steps{grid-template-columns:1fr}
}
@media (max-width:375px){
  body{padding-bottom:92px}
  .logo span{font-size:16px}
}