/* roulang page: index */
:root {
      --c-primary: #2E6FA8;
      --c-primary-dark: #1F4E79;
      --c-primary-deep: #173A5C;
      --c-primary-light: #E8F1F8;
      --c-accent: #C8891A;
      --c-accent-dark: #A06C12;
      --c-asphalt: #1E252E;
      --c-asphalt-2: #262E38;
      --c-concrete: #F4F7FA;
      --c-bg: #F7F9FC;
      --c-white: #FFFFFF;
      --c-text: #1E252E;
      --c-muted: #5B6773;
      --c-line: #D7E2EC;
      --c-reflect: #F4E08A;
      --radius: 12px;
      --radius-sm: 8px;
      --shadow: 0 10px 24px rgba(31, 78, 121, 0.08);
      --shadow-hover: 0 14px 28px rgba(31, 78, 121, 0.14);
      --space: 88px;
      --nav-h: 74px;
      --focus: 0 0 0 3px rgba(46, 111, 168, 0.35);
    }
    *, *::before, *::after { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      font-family: "Noto Sans SC", "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
      font-size: 17px;
      line-height: 1.78;
      color: var(--c-text);
      background: var(--c-bg);
      overflow-x: hidden;
    }
    img { max-width: 100%; height: auto; display: block; }
    a { color: var(--c-primary-dark); text-decoration: none; transition: color .2s ease, transform .2s ease; }
    a:hover { color: var(--c-primary); }
    a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible {
      outline: none;
      box-shadow: var(--focus);
    }
    button, input, select, textarea { font-family: inherit; }
    h1, h2, h3, h4 { letter-spacing: .01em; color: var(--c-asphalt); }
    h2 { font-size: 32px; font-weight: 700; line-height: 1.35; margin: 0 0 14px; }
    h3 { font-size: 20px; font-weight: 700; line-height: 1.4; margin: 0 0 10px; }
    p { margin: 0 0 1em; }
    .skip-link {
      position: absolute; left: 12px; top: -48px; z-index: 2000;
      background: var(--c-accent); color: #fff; padding: 10px 16px; border-radius: 8px;
    }
    .skip-link:focus { top: 10px; color: #fff; }
    .container-site { width: min(1180px, calc(100% - 32px)); margin: 0 auto; }
    .section { padding: 88px 0; }
    .section-tight { padding: 56px 0; }
    .section-head { max-width: 720px; margin-bottom: 36px; }
    .section-head p { color: var(--c-muted); margin: 0; }
    .eyebrow {
      display: inline-flex; align-items: center; gap: 8px;
      color: var(--c-primary-dark); font-size: 13px; font-weight: 600;
      letter-spacing: .08em; margin-bottom: 10px;
    }
    .eyebrow::before { content: ""; width: 18px; height: 2px; background: var(--c-accent); }
    .site-header { background: var(--c-white); }
    .topbar {
      background: var(--c-concrete);
      border-bottom: 1px solid var(--c-line);
      font-size: 13px; color: var(--c-muted);
    }
    .topbar-inner {
      min-height: 40px; display: flex; align-items: center; justify-content: space-between; gap: 16px;
    }
    .topbar a { color: var(--c-primary-dark); font-weight: 600; }
    .topbar-list { display: flex; flex-wrap: wrap; gap: 18px; align-items: center; }
    .topbar-list span { display: inline-flex; align-items: center; gap: 6px; }
    .nav-main {
      position: sticky; top: 0; z-index: 1040;
      background: rgba(255,255,255,.96);
      border-bottom: 1px solid var(--c-line);
      backdrop-filter: saturate(1.1);
    }
    .nav-inner { min-height: var(--nav-h); display: flex; align-items: center; gap: 18px; }
    .brand {
      display: flex; align-items: center; gap: 10px; color: var(--c-asphalt); flex: 0 0 auto;
    }
    .brand:hover { color: var(--c-primary-dark); }
    .brand-mark {
      width: 42px; height: 42px; border-radius: 10px;
      background: linear-gradient(180deg, var(--c-primary) 0%, var(--c-primary-dark) 100%);
      display: grid; place-items: center; color: #fff; box-shadow: 0 6px 14px rgba(31,78,121,.22);
    }
    .brand-text { display: flex; flex-direction: column; line-height: 1.15; }
    .brand-text strong { font-size: 18px; font-weight: 700; }
    .brand-text small { font-size: 12px; color: var(--c-muted); font-weight: 500; }
    .nav-links {
      display: flex; align-items: center; justify-content: center; gap: 4px; flex: 1;
    }
    .nav-links a {
      position: relative; color: var(--c-text); font-size: 15px; font-weight: 500;
      padding: 10px 10px; min-height: 44px; display: inline-flex; align-items: center;
    }
    .nav-links a::after {
      content: ""; position: absolute; left: 10px; right: 10px; bottom: 6px; height: 2px;
      background: var(--c-primary); transform: scaleX(0); transform-origin: left; transition: transform .2s ease;
    }
    .nav-links a:hover, .nav-links a.is-active { color: var(--c-primary-dark); }
    .nav-links a.is-active::after, .nav-links a:hover::after { transform: scaleX(1); }
    .nav-cta { display: flex; align-items: center; gap: 10px; }
    .btn-call-icon {
      display: none; width: 44px; height: 44px; border-radius: 8px;
      background: var(--c-accent); color: #fff; align-items: center; justify-content: center;
    }
    .btn-call-icon:hover { color: #fff; background: var(--c-accent-dark); }
    .menu-toggle {
      display: none; width: 44px; height: 44px; border: 1px solid var(--c-line); background: #fff;
      border-radius: 8px; color: var(--c-asphalt);
    }
    .btn {
      display: inline-flex; align-items: center; justify-content: center; gap: 8px;
      min-height: 44px; padding: 10px 18px; border-radius: var(--radius-sm); border: 0;
      font-weight: 600; font-size: 15px; cursor: pointer; transition: all .18s ease;
    }
    .btn-primary {
      background: var(--c-primary); color: #fff;
      box-shadow: 0 8px 16px rgba(46,111,168,.22);
    }
    .btn-primary:hover { background: var(--c-primary-dark); color: #fff; transform: translateY(-2px); box-shadow: var(--shadow-hover); }
    .btn-primary:active { transform: translateY(1px); }
    .btn-accent {
      background: var(--c-accent); color: #fff;
      box-shadow: 0 8px 16px rgba(200,137,26,.24);
    }
    .btn-accent:hover { background: var(--c-accent-dark); color: #fff; transform: translateY(-2px); }
    .btn-accent:active { transform: translateY(1px); }
    .btn-ghost {
      background: transparent; color: #fff; border: 1px solid rgba(255,255,255,.55);
    }
    .btn-ghost:hover { background: rgba(255,255,255,.12); color: #fff; transform: translateY(-2px); }
    .btn-line {
      background: #fff; color: var(--c-primary-dark); border: 1px solid var(--c-line);
    }
    .btn-line:hover { border-color: var(--c-primary); color: var(--c-primary-dark); transform: translateY(-1px); }
    .mobile-panel {
      display: none; background: #fff; border-top: 1px solid var(--c-line);
    }
    .mobile-panel.open { display: block; }
    .mobile-panel a {
      display: flex; align-items: center; min-height: 48px; padding: 0 8px;
      border-bottom: 1px solid var(--c-concrete); color: var(--c-text); font-weight: 600;
    }
    .hero { position: relative; }
    .hero-carousel, .hero-carousel .carousel-inner, .hero-carousel .carousel-item { height: 84vh; min-height: 620px; }
    .hero-slide {
      height: 84vh; min-height: 620px; background-size: cover; background-position: center 30%;
      position: relative;
    }
    .hero-slide::before {
      content: ""; position: absolute; inset: 0;
      background: linear-gradient(90deg, rgba(30,37,46,.78) 0%, rgba(30,37,46,.55) 48%, rgba(30,37,46,.28) 100%);
    }
    .hero-copy {
      position: relative; z-index: 2; height: 100%;
      display: flex; align-items: center; padding: 40px 0 70px;
    }
    .hero-copy-box { max-width: 640px; color: #fff; }
    .hero-brand {
      display: inline-flex; align-items: center; gap: 8px;
      background: rgba(200,137,26,.16); border: 1px solid rgba(244,224,138,.55);
      color: var(--c-reflect); border-radius: 999px; padding: 6px 12px; font-size: 13px; font-weight: 600; margin-bottom: 16px;
    }
    .hero h1, .hero-title {
      font-size: 42px; line-height: 1.22; font-weight: 700; color: #fff; margin: 0 0 16px;
    }
    .hero-lead { font-size: 16px; line-height: 1.8; color: rgba(255,255,255,.9); margin-bottom: 22px; }
    .check-row { display: grid; grid-template-columns: 1fr 1fr; gap: 8px 16px; margin: 0 0 24px; padding: 0; list-style: none; }
    .check-row li {
      display: flex; align-items: center; gap: 8px; color: #fff; font-size: 14px; font-weight: 500;
    }
    .check-row i { color: var(--c-reflect); font-size: 16px; }
    .hero-actions { display: flex; flex-wrap: wrap; gap: 12px; }
    .carousel-control-prev, .carousel-control-next {
      width: 48px; height: 48px; top: auto; bottom: 28px; opacity: 1; border-radius: 8px;
      background: rgba(30,37,46,.45); border: 1px solid rgba(255,255,255,.2);
    }
    .carousel-control-prev { left: 24px; }
    .carousel-control-next { left: 80px; }
    .carousel-indicators { gap: 8px; margin-bottom: 28px; }
    .carousel-indicators [data-bs-target] {
      width: 10px; height: 10px; border-radius: 50%; background: #fff; opacity: .45; border: 0;
    }
    .carousel-indicators .active { opacity: 1; background: var(--c-accent); }
    .sec-alt { background: #fff; }
    .sec-soft { background: var(--c-primary-light); }
    .bento {
      display: grid; grid-template-columns: repeat(12, 1fr); gap: 18px;
    }
    .svc {
      background: #fff; border: 1px solid var(--c-line); border-radius: var(--radius);
      box-shadow: var(--shadow); padding: 24px; display: flex; flex-direction: column;
      min-height: 220px; transition: transform .2s ease, box-shadow .2s ease;
    }
    .svc:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
    .svc-lg { grid-column: span 6; min-height: 280px; background: linear-gradient(180deg, #fff 70%, var(--c-primary-light) 100%); }
    .svc-sm { grid-column: span 3; }
    .svc-ico {
      width: 46px; height: 46px; border-radius: 10px; display: grid; place-items: center;
      background: var(--c-primary-light); color: var(--c-primary-dark); font-size: 22px; margin-bottom: 14px;
    }
    .svc p { color: var(--c-muted); font-size: 15px; flex: 1; }
    .svc a { font-weight: 600; color: var(--c-primary-dark); min-height: 44px; display: inline-flex; align-items: center; }
    .split { display: grid; grid-template-columns: 5fr 7fr; gap: 40px; align-items: center; }
    .media-frame {
      border-radius: 12px; overflow: hidden; box-shadow: var(--shadow);
      border: 1px solid var(--c-line); background: #fff;
    }
    .media-frame img { width: 100%; height: 420px; object-fit: cover; }
    .spec-list { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 18px; }
    .spec {
      background: var(--c-concrete); border-radius: 10px; padding: 14px 16px;
    }
    .spec b { display: block; font-family: "Roboto Mono", monospace; color: var(--c-primary-dark); font-size: 18px; }
    .spec span { color: var(--c-muted); font-size: 13px; }
    .adv-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
    .adv {
      background: #fff; border-radius: 12px; box-shadow: var(--shadow); padding: 24px;
      border: 1px solid transparent; transition: transform .2s ease, box-shadow .2s ease;
    }
    .adv:hover { transform: translateY(-3px); box-shadow: var(--shadow-hover); border-color: var(--c-primary-light); }
    .adv .num { font-family: "Roboto Mono", monospace; font-size: 28px; color: var(--c-primary); font-weight: 700; }
    .adv p { color: var(--c-muted); font-size: 15px; margin: 0; }
    .equip-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
    .equip {
      background: #fff; border-radius: 12px; overflow: hidden; box-shadow: var(--shadow);
      transition: transform .2s ease, box-shadow .2s ease;
    }
    .equip:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }
    .equip img { width: 100%; height: 230px; object-fit: cover; }
    .equip-body { padding: 20px 20px 22px; }
    .param { display: flex; flex-wrap: wrap; gap: 8px; margin: 12px 0; }
    .tag {
      display: inline-flex; align-items: center; min-height: 28px; padding: 0 10px;
      border-radius: 999px; background: var(--c-primary-light); color: var(--c-primary-dark);
      font-size: 12px; font-weight: 600;
    }
    .tag-amber { background: transparent; border: 1px solid var(--c-accent); color: var(--c-accent-dark); }
    .steps { display: grid; grid-template-columns: repeat(5, 1fr); gap: 16px; position: relative; }
    .step {
      background: #fff; border-radius: 12px; padding: 22px 18px; box-shadow: var(--shadow); position: relative;
    }
    .step::after {
      content: ""; position: absolute; top: 32px; right: -12px; width: 12px; height: 2px; background: var(--c-accent);
    }
    .step:last-child::after { display: none; }
    .step-index {
      width: 36px; height: 36px; border-radius: 8px; background: var(--c-asphalt); color: #fff;
      display: grid; place-items: center; font-family: "Roboto Mono", monospace; font-weight: 700; margin-bottom: 12px;
    }
    .step p { color: var(--c-muted); font-size: 14px; margin: 0; }
    .sec-dark {
      background: var(--c-asphalt); color: #eef3f7;
      border-top: 3px solid var(--c-accent); padding: 88px 0;
    }
    .sec-dark h2, .sec-dark h3 { color: #fff; }
    .sec-dark .section-head p { color: rgba(255,255,255,.78); }
    .case-wall { display: grid; grid-template-columns: 1.3fr 1fr 1fr; grid-auto-rows: 220px; gap: 16px; }
    .case { position: relative; overflow: hidden; border-radius: 12px; }
    .case img { width: 100%; height: 100%; object-fit: cover; }
    .case-wide { grid-row: span 2; height: auto; min-height: 456px; }
    .case figcaption {
      position: absolute; left: 0; right: 0; bottom: 0; padding: 16px;
      background: linear-gradient(180deg, transparent, rgba(30,37,46,.86));
    }
    .case h3 { font-size: 18px; margin: 0 0 6px; }
    .story { display: grid; grid-template-columns: 180px 1fr; gap: 24px; background: #fff; border-radius: 12px; box-shadow: var(--shadow); padding: 22px; margin-bottom: 18px; }
    .story.reverse { grid-template-columns: 1fr 180px; }
    .story.reverse .story-img { order: 2; }
    .story-img { width: 180px; height: 140px; border-radius: 10px; object-fit: cover; }
    .quote { color: var(--c-muted); }
    .stats {
      display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px;
    }
    .stat { text-align: left; padding: 8px 8px 8px 0; }
    .stat b {
      display: block; font-family: "Roboto Mono", monospace; font-size: 40px; line-height: 1.1;
      color: var(--c-primary-dark); font-weight: 700;
    }
    .stat span { color: var(--c-muted); font-size: 14px; }
    .review-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
    .review {
      background: #fff; border-radius: 12px; box-shadow: var(--shadow); padding: 22px 20px; position: relative;
    }
    .review::before { content: "“"; position: absolute; top: 6px; left: 14px; font-size: 42px; color: var(--c-primary-light); }
    .stars { color: var(--c-accent); letter-spacing: 2px; margin-bottom: 8px; }
    .review p { color: var(--c-muted); font-size: 15px; }
    .scene-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
    .scene {
      display: grid; grid-template-columns: 180px 1fr; gap: 18px; background: #fff;
      border-radius: 12px; overflow: hidden; box-shadow: var(--shadow);
    }
    .scene img { width: 180px; height: 100%; min-height: 170px; object-fit: cover; }
    .scene-body { padding: 18px 18px 18px 0; }
    .news-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; }
    .news {
      background: #fff; border-radius: 12px; box-shadow: var(--shadow); overflow: hidden;
      transition: transform .2s ease, box-shadow .2s ease;
    }
    .news:hover { transform: translateY(-3px); box-shadow: var(--shadow-hover); }
    .news img { width: 100%; height: 150px; object-fit: cover; }
    .news-body { padding: 16px 16px 18px; }
    .news h3 { font-size: 17px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
    .news time { color: var(--c-muted); font-size: 13px; font-family: "Roboto Mono", monospace; }
    .news p { color: var(--c-muted); font-size: 14px; margin: 8px 0 0; }
    .logo-wall { display: grid; grid-template-columns: repeat(6, 1fr); gap: 12px; }
    .logo-item {
      min-height: 84px; background: #fff; border: 1px solid var(--c-line); border-radius: 10px;
      display: grid; place-items: center; color: #8a96a3; font-weight: 700; filter: grayscale(1);
      transition: filter .2s ease, color .2s ease, border-color .2s ease;
    }
    .logo-item:hover { filter: none; color: var(--c-primary-dark); border-color: var(--c-primary); }
    .accordion-item { border: 1px solid var(--c-line); border-radius: 10px !important; overflow: hidden; margin-bottom: 10px; background: #fff; }
    .accordion-button { font-weight: 600; min-height: 56px; font-size: 16px; color: var(--c-asphalt); box-shadow: none !important; }
    .accordion-button:not(.collapsed) { background: var(--c-primary-light); color: var(--c-primary-dark); }
    .accordion-button:focus { box-shadow: var(--focus) !important; }
    .accordion-body { color: var(--c-muted); padding-top: 4px; }
    .guarantee {
      display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; margin-bottom: 36px;
    }
    .g-item {
      background: #fff; border-radius: 12px; padding: 18px; box-shadow: var(--shadow);
      display: flex; gap: 12px; align-items: flex-start;
    }
    .g-item i { color: var(--c-accent); font-size: 22px; }
    .contact-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 28px; }
    .form-card, .side-card { background: #fff; border-radius: 12px; box-shadow: var(--shadow); padding: 28px; }
    .form-label { font-weight: 600; margin-bottom: 6px; }
    .form-control, .form-select {
      min-height: 46px; border-radius: 8px; border-color: var(--c-line); font-size: 16px;
    }
    .form-control:focus, .form-select:focus {
      border-color: var(--c-primary); box-shadow: var(--focus);
    }
    textarea.form-control { min-height: 96px; }
    .form-tip { color: var(--c-muted); font-size: 13px; margin-top: 8px; }
    .side-card h3 { margin-bottom: 14px; }
    .side-dl { margin: 0; }
    .side-dl div { display: flex; gap: 10px; padding: 10px 0; border-bottom: 1px solid var(--c-concrete); }
    .side-dl dt { width: 72px; color: var(--c-muted); font-weight: 500; }
    .side-dl dd { margin: 0; font-weight: 600; }
    .site-footer {
      background: var(--c-asphalt-2); color: #c9d3dc; padding: 56px 0 24px;
    }
    .foot-grid { display: grid; grid-template-columns: 1.3fr 1fr 1.2fr 1fr; gap: 28px; margin-bottom: 28px; }
    .site-footer h3 { color: #fff; font-size: 16px; }
    .site-footer a { color: #c9d3dc; display: inline-flex; min-height: 36px; align-items: center; }
    .site-footer a:hover { color: #fff; }
    .foot-copy { border-top: 1px solid rgba(255,255,255,.08); padding-top: 16px; font-size: 13px; }
    .toast-ok {
      display: none; margin-top: 12px; background: var(--c-primary-light); color: var(--c-primary-dark);
      border-radius: 8px; padding: 10px 12px; font-size: 14px;
    }
    @media (max-width: 1199px) {
      .nav-links { gap: 0; }
      .nav-links a { font-size: 14px; padding: 10px 7px; }
      .review-grid, .news-grid { grid-template-columns: repeat(2, 1fr); }
      .logo-wall { grid-template-columns: repeat(3, 1fr); }
    }
    @media (max-width: 1024px) {
      .topbar-list span:nth-child(3), .topbar-list span:nth-child(4) { display: none; }
      .nav-links { display: none; }
      .menu-toggle { display: inline-flex; align-items: center; justify-content: center; }
      .hero h1, .hero-title { font-size: 34px; }
      .split, .contact-grid { grid-template-columns: 1fr; }
      .media-frame img { height: 320px; }
      .svc-lg, .svc-sm { grid-column: span 6; }
      .equip-grid, .adv-grid { grid-template-columns: 1fr 1fr; }
      .steps { grid-template-columns: 1fr 1fr; }
      .step::after { display: none; }
      .case-wall { grid-template-columns: 1fr 1fr; grid-auto-rows: 210px; }
      .case-wide { grid-row: span 1; min-height: 210px; }
      .foot-grid { grid-template-columns: 1fr 1fr; }
      .section { padding: 64px 0; }
    }
    @media (max-width: 768px) {
      .topbar { display: none; }
      .btn-call-icon { display: inline-flex; }
      .nav-cta .btn-accent { display: none; }
      .hero-carousel, .hero-carousel .carousel-inner, .hero-carousel .carousel-item, .hero-slide {
        height: auto; min-height: 640px;
      }
      .check-row { grid-template-columns: 1fr; }
      .bento, .adv-grid, .equip-grid, .stats, .review-grid, .scene-grid, .news-grid, .guarantee, .logo-wall {
        grid-template-columns: 1fr;
      }
      .svc-lg, .svc-sm { grid-column: span 12; }
      .steps { grid-template-columns: 1fr; }
      .step { padding-left: 22px; border-left: 2px solid var(--c-accent); }
      .story, .story.reverse { grid-template-columns: 1fr; }
      .story.reverse .story-img { order: 0; }
      .story-img { width: 100%; height: 180px; }
      .scene { grid-template-columns: 1fr; }
      .scene img { width: 100%; height: 180px; }
      .scene-body { padding: 16px; }
      .case-wall { grid-template-columns: 1fr; }
      .foot-grid { grid-template-columns: 1fr; }
      h2 { font-size: 26px; }
      .section { padding: 48px 0; }
      .carousel-control-prev, .carousel-control-next { bottom: 16px; }
    }
    @media (max-width: 520px) {
      body { font-size: 16px; }
      .hero h1, .hero-title { font-size: 28px; }
      .stat b { font-size: 32px; }
      .container-site { width: min(1180px, calc(100% - 24px)); }
      .hero-actions .btn { width: 100%; }
      .form-card .btn { width: 100%; }
    }