/* ==================================================================
   Yuchuan Air - responsive front-end stylesheet
   No external fonts, no frameworks, no CDN assets: fully portable.
   ================================================================== */

:root {
  --ink: #0d2436;
  --ink-2: #16384f;
  --ink-3: #1d4a63;
  --slate: #5a6f7e;
  --slate-light: #8a9aa6;
  --line: #dde5ea;
  --bg: #f5f8fa;
  --bg-2: #eef3f6;
  --white: #ffffff;
  --accent: #f26522;
  --accent-dark: #d7500f;
  --accent-soft: #fff1e8;
  --blue: #2b7fa8;
  --ok: #1f7a5a;
  --shadow: 0 10px 30px rgba(13, 36, 54, 0.08);
  --shadow-lg: 0 18px 45px rgba(13, 36, 54, 0.14);
  --radius: 6px;
  --maxw: 1240px;
  --font: "Segoe UI", system-ui, -apple-system, Roboto, "Helvetica Neue", Arial, sans-serif;
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.65;
  color: var(--ink);
  background: var(--white);
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
button, input, select, textarea { font: inherit; }
h1, h2, h3, h4 { line-height: 1.2; margin: 0 0 .6em; font-weight: 800; letter-spacing: -.015em; }
p { margin: 0 0 1rem; }
ul { margin: 0 0 1rem; padding-left: 1.2rem; }

:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 999;
  background: var(--accent);
  color: #fff;
  padding: .8rem 1.2rem;
  font-weight: 700;
}
.skip-link:focus { left: 1rem; top: 1rem; }

.container { width: min(100% - 2.5rem, var(--maxw)); margin-inline: auto; }
.container-narrow { width: min(100% - 2.5rem, 860px); margin-inline: auto; }

.section { padding: 5rem 0; }
.section--tight { padding: 3.25rem 0; }
.section--grey { background: var(--bg); }
.section--dark { background: var(--ink); color: #fff; }

.eyebrow {
  display: inline-block;
  color: var(--accent);
  font-size: .78rem;
  font-weight: 800;
  letter-spacing: .16em;
  text-transform: uppercase;
  margin-bottom: .85rem;
}
.section--dark .eyebrow { color: #ff9b5e; }

.section-title { font-size: clamp(1.8rem, 3.4vw, 2.7rem); text-transform: uppercase; }
.section-lead { max-width: 760px; color: var(--slate); font-size: 1.05rem; }
.section--dark .section-lead { color: #c3d3de; }

.section-head { margin-bottom: 2.6rem; }
.section-head--center { text-align: center; }
.section-head--center .section-lead { margin-inline: auto; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: .5rem;
  padding: .85rem 1.6rem;
  border: 2px solid transparent;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: .9rem;
  letter-spacing: .04em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background-color .18s ease, color .18s ease, border-color .18s ease, transform .18s ease;
}
.btn:hover { transform: translateY(-2px); }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-dark); }
.btn-outline { background: transparent; color: #fff; border-color: rgba(255,255,255,.7); }
.btn-outline:hover { background: #fff; color: var(--ink); border-color: #fff; }
.btn-outline-dark { background: transparent; color: var(--ink); border-color: var(--ink-2); }
.btn-outline-dark:hover { background: var(--ink); color: #fff; }
.btn-small { padding: .6rem 1.1rem; font-size: .8rem; }
.btn:disabled { opacity: .6; cursor: not-allowed; transform: none; }

/* ---------------- Header ---------------- */

.topbar {
  background: var(--ink);
  color: #c8d7e0;
  font-size: .8rem;
  border-bottom: 1px solid rgba(255,255,255,.08);
}
.topbar .container { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 38px; }
.topbar-left { display: flex; align-items: center; gap: 1.4rem; flex-wrap: wrap; }
.topbar a { color: #c8d7e0; }
.topbar a:hover { color: #fff; }
.topbar strong { color: var(--accent); font-weight: 700; }

.site-header { position: sticky; top: 0; z-index: 100; background: #fff; box-shadow: 0 2px 14px rgba(13,36,54,.09); }
.header-inner { display: flex; align-items: center; gap: 1.5rem; min-height: 78px; }

.brand { display: inline-flex; align-items: center; gap: .75rem; flex: 0 0 auto; }
.brand-mark { width: 42px; height: 42px; flex: 0 0 42px; }
.brand-text { display: flex; flex-direction: column; line-height: 1.1; }
.brand-name { font-size: 1.15rem; font-weight: 900; letter-spacing: -.02em; color: var(--ink); text-transform: uppercase; }
.brand-sub { font-size: .64rem; letter-spacing: .13em; text-transform: uppercase; color: var(--slate); margin-top: .25rem; }

.main-nav { margin-left: auto; }
.main-nav > ul { list-style: none; margin: 0; padding: 0; display: flex; align-items: center; gap: .25rem; }
.main-nav li { position: relative; }
.main-nav a {
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  padding: .7rem .85rem;
  font-size: .88rem;
  font-weight: 700;
  color: var(--ink-2);
  border-radius: 4px;
  text-transform: uppercase;
  letter-spacing: .03em;
  white-space: nowrap;
}
.main-nav a:hover, .main-nav a[aria-current="page"] { color: var(--accent); background: var(--accent-soft); }
.main-nav .has-sub > a::after { content: ""; width: 6px; height: 6px; border-right: 2px solid currentColor; border-bottom: 2px solid currentColor; transform: rotate(45deg) translateY(-2px); }
.submenu {
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 265px;
  background: #fff;
  border: 1px solid var(--line);
  border-top: 3px solid var(--accent);
  box-shadow: var(--shadow-lg);
  padding: .5rem 0;
  display: none;
  z-index: 110;
}
.main-nav .has-sub:hover .submenu,
.main-nav .has-sub:focus-within .submenu { display: block; }
.submenu a { display: block; padding: .55rem 1.1rem; font-size: .84rem; text-transform: none; letter-spacing: 0; font-weight: 600; }
.submenu a:hover { background: var(--bg); }

.header-cta { flex: 0 0 auto; }
.nav-toggle {
  display: none;
  margin-left: auto;
  width: 44px; height: 44px;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 4px;
  cursor: pointer;
  padding: 0;
  align-items: center;
  justify-content: center;
}
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--ink); position: relative; }
.nav-toggle span::before, .nav-toggle span::after { content: ""; position: absolute; left: 0; width: 22px; height: 2px; background: var(--ink); }
.nav-toggle span::before { top: -7px; }
.nav-toggle span::after { top: 7px; }

.nav-close { display: none; }
.nav-overlay { display: none; }

/* ---------------- Hero ---------------- */

.hero {
  position: relative;
  overflow: hidden;
  background: linear-gradient(115deg, #0b2031 0%, #16384f 55%, #1e4f68 100%);
  color: #fff;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(rgba(255,255,255,.045) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.045) 1px, transparent 1px);
  background-size: 52px 52px;
  mask-image: linear-gradient(90deg, transparent, #000 40%, #000);
  pointer-events: none;
}
.hero::after {
  content: "";
  position: absolute;
  width: 480px; height: 480px;
  right: -160px; top: -180px;
  background: radial-gradient(circle, rgba(242,101,34,.28), transparent 65%);
  pointer-events: none;
}
.hero-inner { position: relative; display: grid; grid-template-columns: 1.08fr .92fr; gap: 3rem; align-items: center; padding-block: 5.5rem 6rem; }
.hero-badge {
  display: inline-flex; align-items: center; gap: .5rem;
  background: rgba(242,101,34,.16);
  border: 1px solid rgba(242,101,34,.55);
  color: #ffb98d;
  padding: .45rem .9rem;
  border-radius: 100px;
  font-size: .76rem; font-weight: 800; letter-spacing: .1em; text-transform: uppercase;
  margin-bottom: 1.4rem;
}
.hero-badge::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: var(--accent); }
.hero h1 { font-size: clamp(2.3rem, 5.2vw, 4.1rem); text-transform: uppercase; letter-spacing: -.03em; line-height: 1.05; margin-bottom: 1.3rem; }
.hero h1 span { color: #ff8a45; }
.hero-text { color: #c8d9e4; font-size: 1.05rem; max-width: 620px; margin-bottom: 2rem; }
.hero-actions { display: flex; flex-wrap: wrap; gap: .9rem; }
.hero-art { position: relative; }
.hero-art svg { width: 100%; height: auto; filter: drop-shadow(0 25px 40px rgba(0,0,0,.35)); }
.hero-scene {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  object-position: 62% center;
  border: 1px solid rgba(255,255,255,.18);
  border-radius: 6px;
  box-shadow: 0 25px 50px rgba(0,0,0,.3);
}

/* ---------------- Stats strip ---------------- */

.stats-strip { background: var(--accent); color: #fff; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); }
.stat { padding: 1.7rem 1.2rem; text-align: center; border-right: 1px solid rgba(255,255,255,.24); }
.stat:last-child { border-right: 0; }
.stat-value { font-size: clamp(1.6rem, 3vw, 2.3rem); font-weight: 900; line-height: 1; letter-spacing: -.03em; }
.stat-label { font-size: .76rem; text-transform: uppercase; letter-spacing: .1em; margin-top: .5rem; opacity: .92; }

/* ---------------- Cards ---------------- */

.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
.card-grid--4 { grid-template-columns: repeat(4, 1fr); }

.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}
.card:hover { transform: translateY(-5px); box-shadow: var(--shadow-lg); border-color: #c9d7df; }
.card-visual {
  aspect-ratio: 4 / 3;
  background: linear-gradient(145deg, #f0f5f8, #e2ebf0);
  display: grid;
  place-items: center;
  overflow: hidden;
  position: relative;
}
.card-visual svg { width: 82%; height: 82%; }
.card-visual img { width: 100%; height: 100%; object-fit: cover; }
.card-visual::after { content: ""; position: absolute; inset: auto 0 0 0; height: 3px; background: var(--accent); transform: scaleX(0); transform-origin: left; transition: transform .25s ease; }
.card:hover .card-visual::after { transform: scaleX(1); }

.card-body { padding: 1.4rem 1.4rem 1.6rem; display: flex; flex-direction: column; flex: 1; }
.card-series { font-size: .7rem; font-weight: 800; letter-spacing: .14em; text-transform: uppercase; color: var(--accent); margin-bottom: .55rem; }
.product-status { color: var(--slate); font-size: .72rem; font-weight: 700; letter-spacing: .035em; margin: -.1rem 0 .6rem; }
.card-title { font-size: 1.08rem; font-weight: 800; margin-bottom: .6rem; line-height: 1.3; }
.card-title a:hover { color: var(--accent); }
.card-text { color: var(--slate); font-size: .9rem; flex: 1; margin-bottom: 1.2rem; }
.card-link { display: inline-flex; align-items: center; gap: .45rem; font-size: .78rem; font-weight: 800; text-transform: uppercase; letter-spacing: .07em; color: var(--accent); }
.card-link::after { content: "\2192"; font-size: 1.05rem; line-height: 1; transition: transform .2s ease; }
.card-link:hover::after { transform: translateX(5px); }

/* Category tile */
.tile-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 1rem; }
.tile {
  display: flex; flex-direction: column;
  background: #fff; border: 1px solid var(--line); border-radius: var(--radius);
  padding: 1.3rem 1.2rem;
  transition: border-color .2s ease, box-shadow .2s ease, transform .2s ease;
}
.tile:hover { border-color: var(--accent); box-shadow: var(--shadow); transform: translateY(-3px); }
.tile-icon { width: 42px; height: 42px; border-radius: 5px; background: var(--accent-soft); color: var(--accent); display: grid; place-items: center; margin-bottom: .9rem; }
.tile-icon svg { width: 24px; height: 24px; }
.tile-name { font-size: .93rem; font-weight: 800; margin-bottom: .35rem; line-height: 1.3; }
.tile-count { font-size: .75rem; color: var(--slate-light); text-transform: uppercase; letter-spacing: .08em; margin-top: auto; }

/* Application card */
.app-card { background: #fff; border: 1px solid var(--line); border-left: 4px solid var(--accent); border-radius: var(--radius); padding: 1.6rem; }
.app-card h3 { font-size: 1.05rem; margin-bottom: .6rem; }
.app-card p { color: var(--slate); font-size: .9rem; margin: 0; }

/* Resource card */
.resource-card { display: block; background: var(--white); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.7rem; transition: box-shadow .2s ease, transform .2s ease; }
.resource-card:hover { box-shadow: var(--shadow); transform: translateY(-3px); }
.resource-num { font-size: .75rem; font-weight: 800; color: var(--accent); letter-spacing: .14em; }
.resource-card h3 { font-size: 1.05rem; margin: .6rem 0 .55rem; }
.resource-card p { color: var(--slate); font-size: .88rem; margin: 0 0 1rem; }
.resource-more { font-size: .78rem; font-weight: 800; text-transform: uppercase; letter-spacing: .08em; color: var(--accent); }

/* ---------------- Content blocks ---------------- */

.split { display: grid; grid-template-columns: 1fr 1fr; gap: 3.2rem; align-items: center; }
.split-visual { background: linear-gradient(145deg, #e9f1f5, #d7e5ec); border-radius: var(--radius); padding: 2rem; }
.split-visual svg { width: 100%; height: auto; }

.check-list { list-style: none; padding: 0; margin: 1.4rem 0 0; }
.check-list li { position: relative; padding-left: 1.8rem; margin-bottom: .75rem; color: var(--slate); }
.check-list li::before {
  content: "\2713"; position: absolute; left: 0; top: .05rem;
  width: 20px; height: 20px; border-radius: 50%;
  background: var(--accent-soft); color: var(--accent);
  font-size: .7rem; font-weight: 900; display: grid; place-items: center;
}

.cta-band { background: linear-gradient(115deg, var(--ink) 0%, var(--ink-3) 100%); color: #fff; padding: 3.6rem 0; position: relative; overflow: hidden; }
.cta-band::after { content: ""; position: absolute; right: -80px; bottom: -160px; width: 380px; height: 380px; background: radial-gradient(circle, rgba(242,101,34,.25), transparent 65%); }
.cta-inner { position: relative; display: flex; align-items: center; justify-content: space-between; gap: 2rem; flex-wrap: wrap; }
.cta-inner h2 { font-size: clamp(1.6rem, 3vw, 2.3rem); text-transform: uppercase; margin-bottom: .6rem; }
.cta-inner p { color: #c4d5df; max-width: 640px; margin: 0; }

/* ---------------- Product list / filters ---------------- */

.page-hero { background: var(--ink); color: #fff; padding: 3.4rem 0 3.6rem; position: relative; overflow: hidden; }
.page-hero::after { content: ""; position: absolute; inset: 0; background-image: linear-gradient(rgba(255,255,255,.04) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.04) 1px, transparent 1px); background-size: 48px 48px; pointer-events: none; }
.page-hero .container { position: relative; }
.page-hero h1 { font-size: clamp(2rem, 4.4vw, 3.2rem); text-transform: uppercase; margin-bottom: .7rem; }
.page-hero p { color: #c2d4df; max-width: 720px; margin: 0; }
.breadcrumb { font-size: .8rem; color: #9db4c2; margin-bottom: 1rem; }
.breadcrumb a:hover { color: #fff; }
.breadcrumb span { margin: 0 .45rem; }

.toolbar { display: flex; gap: 1rem; flex-wrap: wrap; align-items: center; margin-bottom: 2rem; padding: 1.1rem; background: var(--bg); border: 1px solid var(--line); border-radius: var(--radius); }
.toolbar label { font-size: .76rem; font-weight: 800; text-transform: uppercase; letter-spacing: .08em; color: var(--slate); display: block; margin-bottom: .35rem; }
.toolbar select, .toolbar input[type="search"] {
  min-width: 220px; padding: .65rem .8rem; border: 1px solid var(--line); border-radius: 4px;
  background: #fff; color: var(--ink); font-size: .9rem;
}
.toolbar .field { flex: 1 1 240px; }
.toolbar .field--small { flex: 0 1 280px; }
.result-count { font-size: .85rem; color: var(--slate); margin-bottom: 1.2rem; }

/* ---------------- Product detail ---------------- */

.detail-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 3rem; align-items: start; }
.detail-visual { background: linear-gradient(145deg, #eef4f7, #dde9ef); border-radius: var(--radius); padding: 2rem; border: 1px solid var(--line); }
.detail-visual svg { width: 100%; height: auto; }
.detail-visual img { width: 100%; border-radius: 4px; }
.detail-series { color: var(--accent); font-weight: 800; font-size: .78rem; letter-spacing: .14em; text-transform: uppercase; margin-bottom: .7rem; }
.detail-title { font-size: clamp(1.7rem, 3.2vw, 2.5rem); text-transform: uppercase; }
.detail-summary { font-size: 1.08rem; color: var(--slate); }
.catalogue-notice { margin: 0 auto 1rem; padding: 1rem 1.2rem; border-left: 4px solid var(--accent); background: var(--accent-soft); color: var(--ink-2); font-size: .92rem; line-height: 1.65; }
.catalogue-notice strong { color: var(--ink); }
.spec-table { width: 100%; border-collapse: collapse; margin-top: 1rem; }
.spec-table th, .spec-table td { text-align: left; padding: .8rem .9rem; border-bottom: 1px solid var(--line); font-size: .92rem; }
.spec-table th { width: 38%; background: var(--bg); font-weight: 700; color: var(--ink-2); }
.tag { display: inline-block; background: var(--bg-2); border: 1px solid var(--line); color: var(--ink-2); border-radius: 100px; padding: .35rem .8rem; font-size: .8rem; margin: 0 .4rem .4rem 0; }

/* ---------------- Article ---------------- */

.article { max-width: 800px; margin-inline: auto; }
.article-meta { color: var(--slate); font-size: .85rem; margin-bottom: 1.4rem; }
.article-body { font-size: 1.05rem; color: #2c4354; }
.article-body h2 { font-size: 1.5rem; margin-top: 2.2rem; text-transform: none; }
.article-body h3 { font-size: 1.18rem; margin-top: 1.6rem; text-transform: none; }
.article-body li { margin-bottom: .5rem; }
.post-card { display: flex; flex-direction: column; }
.post-meta { font-size: .76rem; color: var(--slate-light); text-transform: uppercase; letter-spacing: .08em; margin-bottom: .6rem; }
.post-cover { aspect-ratio: 16 / 9; background: linear-gradient(140deg, #dfeaf0, #cadde6); display: grid; place-items: center; }
.post-cover img { width: 100%; height: 100%; object-fit: cover; }
.post-cover svg { width: 55%; height: 55%; }

/* ---------------- Contact ---------------- */

.contact-grid { display: grid; grid-template-columns: 1fr 1.1fr; gap: 3rem; align-items: start; }
.info-row { display: flex; gap: 1rem; padding: 1.1rem 0; border-bottom: 1px solid var(--line); }
.info-icon { width: 40px; height: 40px; flex: 0 0 40px; border-radius: 5px; background: var(--accent-soft); color: var(--accent); display: grid; place-items: center; }
.info-icon svg { width: 20px; height: 20px; }
.info-row h3 { font-size: .78rem; text-transform: uppercase; letter-spacing: .1em; color: var(--slate); margin-bottom: .2rem; }
.info-row p { margin: 0; font-weight: 600; word-break: break-word; }

.form-card { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 2rem; box-shadow: var(--shadow); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.form-field { margin-bottom: 1.1rem; }
.form-field label { display: block; font-size: .8rem; font-weight: 700; margin-bottom: .4rem; color: var(--ink-2); }
.form-field label span { color: var(--accent); }
.form-field input, .form-field select, .form-field textarea {
  width: 100%; padding: .75rem .85rem; border: 1px solid var(--line); border-radius: 4px;
  background: #fff; color: var(--ink); font-size: .92rem;
}
.form-field textarea { min-height: 130px; resize: vertical; }
.form-field input:focus, .form-field select:focus, .form-field textarea:focus { border-color: var(--accent); }
.form-note { font-size: .8rem; color: var(--slate); margin-top: .8rem; }
.form-status { margin-top: 1rem; padding: .85rem 1rem; border-radius: 4px; font-size: .9rem; display: none; }
.form-status.is-visible { display: block; }
.form-status.is-ok { background: #e7f6ef; color: var(--ok); border: 1px solid #b9e4d1; }
.form-status.is-error { background: #fdecec; color: #a12a20; border: 1px solid #f3c2bd; }

/* ---------------- Footer ---------------- */

.site-footer { background: var(--ink); color: #c5d5df; padding-top: 3.8rem; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1.25fr; gap: 2.4rem; padding-bottom: 3rem; }
.site-footer h3 { color: #fff; font-size: .85rem; letter-spacing: .12em; text-transform: uppercase; margin-bottom: 1.2rem; }
.footer-brand { display: flex; align-items: flex-start; gap: .8rem; margin-bottom: 1.2rem; }
.footer-brand .brand-mark { width: 38px; height: 38px; flex-basis: 38px; }
.footer-brand .brand-name { color: #fff; font-size: 1rem; }
.footer-brand .brand-sub { color: #8ba4b4; }
.site-footer p { font-size: .88rem; line-height: 1.7; }
.footer-links { list-style: none; padding: 0; margin: 0; }
.footer-links li { margin-bottom: .55rem; }
.footer-links a { font-size: .88rem; }
.footer-links a:hover { color: var(--accent); }
.footer-contact li { display: flex; gap: .6rem; font-size: .88rem; margin-bottom: .8rem; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,.12); padding: 1.3rem 0; font-size: .8rem; display: flex; justify-content: space-between; gap: 1rem; flex-wrap: wrap; }
.footer-bottom a:hover { color: var(--accent); }

/* ---------------- Utilities ---------------- */

.loading { color: var(--slate); padding: 2rem 0; font-size: .92rem; }
.empty-state { padding: 3rem 1rem; text-align: center; color: var(--slate); border: 1px dashed var(--line); border-radius: var(--radius); }
.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }
.text-center { text-align: center; }
.center-actions { display: flex; justify-content: center; gap: .9rem; flex-wrap: wrap; margin-top: 2.4rem; }

/* ---------------- Responsive ---------------- */

@media (max-width: 1100px) {
  .tile-grid { grid-template-columns: repeat(3, 1fr); }
  .card-grid--4 { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1.4fr 1fr 1fr; }
  .footer-grid > div:last-child { grid-column: 1 / -1; }
}

@media (max-width: 980px) {
  .header-inner { min-height: 68px; }
  .nav-toggle { display: flex; }
  .header-cta { display: none; }
  .main-nav {
    position: fixed;
    top: 0; right: 0;
    width: min(340px, 86vw);
    height: 100dvh;
    background: #fff;
    z-index: 210;
    padding: 5rem 1.2rem 2rem;
    overflow-y: auto;
    box-shadow: -12px 0 40px rgba(0,0,0,.25);
    transform: translateX(105%);
    transition: transform .25s ease;
    margin-left: 0;
  }
  .main-nav.is-open { transform: translateX(0); }
  .main-nav > ul { display: block; }
  .main-nav > ul > li { border-bottom: 1px solid var(--line); }
  .main-nav a { display: flex; justify-content: space-between; width: 100%; padding: .9rem .5rem; font-size: .95rem; }
  .submenu { position: static; display: block !important; box-shadow: none; border: 0; border-left: 2px solid var(--accent-soft); min-width: 0; padding: 0 0 .5rem .8rem; }
  .submenu a { font-size: .85rem; padding: .45rem .3rem; }
  .nav-overlay {
    display: block; position: fixed; inset: 0; z-index: 200;
    background: rgba(9, 25, 37, .55); opacity: 0; pointer-events: none;
    transition: opacity .25s ease;
  }
  .nav-overlay.is-open { opacity: 1; pointer-events: auto; }
  .nav-close {
    display: block;
    position: absolute; top: 1rem; right: 1rem;
    width: 40px; height: 40px; border: 1px solid var(--line);
    background: #fff; border-radius: 4px; cursor: pointer;
    font-size: 1.3rem; line-height: 1; color: var(--ink);
  }
  .hero-inner { grid-template-columns: 1fr; padding-block: 3.6rem 4.2rem; }
  .hero-art { max-width: 460px; margin-inline: auto; order: -1; }
  .split, .detail-grid, .contact-grid { grid-template-columns: 1fr; gap: 2rem; }
  .split-visual { order: -1; }
  .card-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .stat:nth-child(2) { border-right: 0; }
  .stat:nth-child(-n+2) { border-bottom: 1px solid rgba(255,255,255,.24); }
  .section { padding: 3.6rem 0; }
}

@media (max-width: 640px) {
  body { font-size: 15px; }
  .container, .container-narrow { width: min(100% - 1.6rem, var(--maxw)); }
  .topbar .container { justify-content: center; }
  .topbar-left { justify-content: center; gap: .8rem; }
  .topbar-left span:last-child { display: none; }
  .hero h1 { font-size: 2.1rem; }
  .hero-actions .btn { width: 100%; }
  .card-grid, .card-grid--4, .tile-grid { grid-template-columns: 1fr; }
  .form-row { grid-template-columns: 1fr; }
  .toolbar .field, .toolbar .field--small { flex: 1 1 100%; }
  .toolbar select, .toolbar input[type="search"] { width: 100%; min-width: 0; }
  .footer-grid { grid-template-columns: 1fr; gap: 1.8rem; }
  .footer-grid > div:last-child { grid-column: auto; }
  .cta-inner { flex-direction: column; align-items: flex-start; }
  .section { padding: 3rem 0; }
  .form-card { padding: 1.4rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: .01ms !important; animation-duration: .01ms !important; }
}

/* ------------------------------------------------------------------
   GEO / FAQ blocks and lead-attribution honeypot
   These blocks are real, visible content - not hidden keyword text.
   ------------------------------------------------------------------ */
.geo-answer {
  font-size: 1.05rem;
  line-height: 1.75;
  padding: 1rem 1.2rem;
  border-left: 4px solid var(--orange, #f26522);
  background: #f7fafb;
  margin: 0 0 1.5rem;
}
.faq-section { border-top: 1px solid var(--line, #dde5ea); }
.faq-list { max-width: 820px; margin: 0 auto; }
.faq-item {
  background: #fff;
  border: 1px solid var(--line, #dde5ea);
  border-radius: 6px;
  margin-bottom: .7rem;
  padding: 0 1.2rem;
}
.faq-item[open] { border-color: #b9cdd8; }
.faq-q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  cursor: pointer;
  list-style: none;
  padding: 1rem 0;
}
.faq-q::-webkit-details-marker { display: none; }
.faq-q h3 { font-size: 1rem; margin: 0; text-transform: none; letter-spacing: 0; }
.faq-toggle { color: var(--orange, #f26522); font-size: 1.5rem; line-height: 1; flex: 0 0 auto; }
.faq-item[open] .faq-toggle { transform: rotate(45deg); }
.faq-a { padding: 0 0 1.1rem; color: #4c6272; line-height: 1.75; }
.faq-a p { margin: 0; }
.hp-field {
  position: absolute !important;
  left: -9999px !important;
  width: 1px; height: 1px;
  overflow: hidden;
}
@media (max-width: 640px) {
  .faq-q h3 { font-size: .95rem; }
  .geo-answer { font-size: .98rem; }
}

/* ------------------------------------------------------------------
   Cookie consent banner (Consent Mode v2 / EU-UK compliance)
   ------------------------------------------------------------------ */
.yc-consent {
  position: fixed;
  left: 0; right: 0; bottom: 0;
  z-index: 9999;
  padding: 1rem 1.25rem calc(1rem + env(safe-area-inset-bottom, 0px));
  background: var(--white);
  border-top: 2px solid var(--accent);
  box-shadow: 0 -8px 30px rgba(13, 36, 54, .14);
}
.yc-consent-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}
.yc-consent-text { min-width: 0; }
.yc-consent-text strong {
  display: block;
  font-size: .95rem;
  color: var(--ink);
  margin-bottom: .15rem;
}
.yc-consent-text p {
  margin: 0;
  font-size: .85rem;
  line-height: 1.55;
  color: var(--slate);
  max-width: 760px;
}
.yc-consent-text a {
  color: var(--blue);
  text-decoration: underline;
  text-underline-offset: 2px;
}
.yc-consent-text a:hover { color: var(--accent-dark); }
.yc-consent-actions {
  display: flex;
  gap: .6rem;
  flex: 0 0 auto;
  align-items: center;
}
.yc-consent-actions .btn { white-space: nowrap; }
.yc-consent :focus-visible {
  outline: 3px solid var(--blue);
  outline-offset: 2px;
}
.form-note a, .footer-bottom a { text-decoration: underline; text-underline-offset: 2px; }
.form-note a:hover, .footer-bottom a:hover { color: var(--accent-dark); }
.footer-bottom { flex-wrap: wrap; gap: .4rem 1rem; }
@media (max-width: 760px) {
  .yc-consent-inner { flex-direction: column; align-items: stretch; gap: .8rem; }
  .yc-consent-actions { justify-content: stretch; }
  .yc-consent-actions .btn { flex: 1; }
  .yc-consent-text p { font-size: .82rem; }
}


/* ------------------------------------------------------------------
   Editorial and illustrative content imagery
   ------------------------------------------------------------------ */
.image-disclaimer {
  color: #526b7c;
  font-size: .75rem;
  line-height: 1.5;
  margin: .75rem 0 0;
}
.image-disclaimer--overlay {
  position: absolute;
  z-index: 2;
  left: .5rem;
  right: .5rem;
  bottom: .5rem;
  padding: .4rem .55rem;
  border-radius: 3px;
  background: rgba(13, 36, 54, .9);
  color: #fff;
  font-size: .69rem;
  line-height: 1.35;
  text-align: center;
}
.tile-visual {
  display: block;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  margin: -.45rem -.35rem .9rem;
  border-radius: 4px;
  background: linear-gradient(145deg, #eef4f7, #dce8ee);
}
.tile-visual img { width: 100%; height: 100%; object-fit: cover; }
.app-card { overflow: hidden; padding: 0; }
.app-card-visual { aspect-ratio: 16 / 9; overflow: hidden; position: relative; background: #e5edf1; }
.app-card-visual img { width: 100%; height: 100%; object-fit: cover; }
.app-card-body { padding: 1.25rem 1.4rem 1.5rem; }
.collection-cover {
  width: min(100%, 560px);
  aspect-ratio: 4 / 3;
  margin: 1.35rem 0 0;
  overflow: hidden;
  border: 1px solid rgba(255,255,255,.18);
  border-radius: 6px;
  background: rgba(255,255,255,.06);
}
.collection-cover:empty { display: none; }
.collection-cover img { width: 100%; height: 100%; object-fit: cover; }
.collection-cover .image-disclaimer { margin: 0; padding: .45rem .65rem; background: rgba(13,36,54,.9); color: #fff; }
.article-cover-detail { margin: 1.5rem 0 2rem; overflow: hidden; border-radius: 6px; }
.article-cover-detail img { width: 100%; height: auto; aspect-ratio: 16 / 9; object-fit: cover; }
.article-cover-detail .image-disclaimer { padding: 0 .1rem; }
.page-image-note { margin: .8rem 0 0 !important; color: #c3d3de !important; font-size: .82rem !important; }
@media (max-width: 640px) {
  .tile-visual { aspect-ratio: 16 / 9; }
  .collection-cover { width: 100%; }
}

.tile-visual { position: relative; }
.tile-visual .image-disclaimer--overlay { font-size: .66rem; }

.collection-cover { position: relative; }
.collection-cover .image-disclaimer { position: absolute; left: 0; right: 0; bottom: 0; z-index: 2; }


/* ---------------- Answer-first SEO / GEO articles ---------------- */
.post-shell-lead { max-width: 52rem; margin-top: 1rem; color: #d0dde5; }
.article--longform { max-width: 820px; }
.article-header { margin-bottom: 1.8rem; }
.article-title { max-width: 20ch; font-size: clamp(2rem, 4vw, 3rem); line-height: 1.12; text-transform: none; letter-spacing: -.025em; }
.article-header .geo-answer { margin: 1.2rem 0 0; padding: 1.1rem 1.2rem; border-left: 4px solid var(--accent); background: var(--bg-2); color: var(--ink-2); font-size: 1.06rem; line-height: 1.72; }
.article-header .geo-answer strong { color: var(--ink); }
.article-takeaways { margin: 1.5rem 0; padding: 1.15rem 1.3rem; border: 1px solid var(--line); border-radius: 6px; background: var(--bg); }
.article-takeaways h2, .article-toc h2, .article-sources h2, .article-faqs h2 { margin: 0 0 .8rem; color: var(--ink); font-size: 1.15rem; text-transform: none; }
.article-takeaways ul { margin: 0; padding-left: 1.25rem; }
.article-takeaways li { margin: .45rem 0; line-height: 1.6; }
.article-toc { margin: 1.6rem 0 2rem; padding: 1.15rem 1.3rem; border: 1px solid var(--line); border-radius: 6px; }
.article-toc ol { margin: 0; padding-left: 1.35rem; columns: 2; column-gap: 2.5rem; }
.article-toc li { break-inside: avoid; margin: .4rem 0; line-height: 1.5; }
.article-toc a { color: var(--ink-2); text-decoration-thickness: 1px; text-underline-offset: .16em; }
.article-toc a:hover { color: var(--accent); }
.article-toc a:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
.article-body { line-height: 1.82; }
.article-body p { margin: 1rem 0; }
.article-body h2 { scroll-margin-top: 6rem; line-height: 1.3; }
.article-body h3 { line-height: 1.35; }
.article-body a, .article-sources a { color: var(--accent); text-underline-offset: .16em; }
.article-body blockquote { margin: 1.4rem 0; padding: .5rem 1.1rem; border-left: 3px solid var(--accent); color: var(--ink-2); background: var(--bg); }
.article-sources { margin: 2.6rem 0 1rem; padding-top: 1.4rem; border-top: 1px solid var(--line); }
.article-sources ol { padding-left: 1.3rem; }
.article-sources li { margin: .9rem 0 1.1rem; padding-left: .2rem; line-height: 1.55; }
.article-sources li > a { font-weight: 700; }
.article-sources .source-meta, .article-sources .source-relevance { margin: .25rem 0 0; color: var(--slate); font-size: .88rem; }
.article-sources .source-note { margin-top: 1rem; color: var(--slate); font-size: .88rem; }
.article-faqs { margin: 2.5rem 0 1rem; padding-top: 1.4rem; border-top: 1px solid var(--line); }
.article-faqs h2 { font-size: 1.4rem; }
.article-faqs .faq-item { border-bottom: 1px solid var(--line); }
@media (max-width: 640px) {
  .article-toc ol { columns: 1; }
  .article-takeaways, .article-toc { padding: 1rem; }
  .article-title { max-width: none; }
}

/* UCHAN identity: one original lockup, shared by all public pages. */
.brand-logo { display: block; width: 172px; height: auto; max-width: 100%; object-fit: contain; }
.brand .brand-text { gap: 3px; }
.brand .brand-sub { margin-top: 0; font-size: .57rem; letter-spacing: .13em; }
.footer-brand { flex-direction: column; gap: .65rem; }
.brand-logo-surface { display: inline-flex; padding: 10px 12px; background: #fff; border-radius: 4px; }
.footer-brand .brand-logo { width: 180px; }
.footer-brand .brand-sub { max-width: 240px; font-size: .6rem; line-height: 1.6; }
@media (max-width: 600px) {
  .brand-logo { width: 145px; }
  .brand .brand-sub { font-size: .5rem; }
}

/* Accessibility: preserve engineering orange for surfaces; use dark orange for text. */
:root {
  --accent-text: #b83e06;
  --accent-dark: #b83e06;
  --slate-light: #526674;
  --control-border: #788b99;
  --blue: #21688c;
}
[hidden] { display: none !important; }
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip-path: inset(50%);
  white-space: nowrap; border: 0;
}
:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 3px;
  box-shadow: 0 0 0 3px #fff;
}
main, [id] { scroll-margin-top: 6.5rem; }
.skip-link { background: var(--ink); color: #fff; z-index: 10001; }
.btn-primary { color: var(--ink); }
.btn-primary:hover, .btn-primary:active { background: var(--accent-dark); color: #fff; }
.stats-strip { color: var(--ink); }
.stat-label { opacity: 1; }
.eyebrow, .card-series, .card-link, .resource-num, .resource-more,
.detail-series, .article-body a, .article-sources a, .required-marker,
.form-field label span { color: var(--accent-text); }
.main-nav a:hover, .main-nav a[aria-current="page"], .card-title a:hover,
.article-toc a:hover { color: var(--accent-text); }
.section--dark .check-list li { color: #c3d3de; }
.check-list li::before, .tile-icon, .info-icon, .faq-toggle { color: var(--accent-text); }
.article-body a, .article-sources a, .article-toc a, .empty-state a {
  text-decoration: underline;
  text-underline-offset: .16em;
}
.footer-links a:hover, .footer-bottom a:hover { color: #ffb98d; }
.toolbar select, .toolbar input[type="search"],
.form-field input, .form-field select, .form-field textarea,
.nav-toggle, .nav-close { border-color: var(--control-border); }
input::placeholder, textarea::placeholder { color: #526674; opacity: 1; }
input[type="checkbox"], input[type="radio"] { accent-color: var(--accent-text); }
.main-nav .has-sub { display: flex; align-items: center; flex-wrap: wrap; }
.main-nav .has-sub > a::after { content: none; }
.submenu-toggle {
  display: inline-flex; align-items: center; justify-content: center;
  width: 36px; height: 36px; padding: 0;
  border: 1px solid var(--control-border); border-radius: 4px;
  background: #fff; color: var(--ink); cursor: pointer;
  font-size: 1.4rem; line-height: 1;
}
.submenu-toggle:hover { background: var(--accent-soft); }
.submenu-toggle[aria-expanded="true"] span { transform: rotate(180deg); }
.main-nav .submenu { display: block; }
.card:focus-within, .resource-card:focus-visible, .tile:focus-visible { border-color: var(--ink); }
.card-visual:focus-visible { outline-offset: -4px; box-shadow: inset 0 0 0 7px #fff; }
.yc-consent :focus-visible, .article-toc a:focus-visible {
  outline: 3px solid var(--ink); outline-offset: 3px; box-shadow: 0 0 0 3px #fff;
}
@media (max-width: 980px) {
  .main-nav { visibility: hidden; }
  .main-nav.is-open { visibility: visible; }
  .main-nav .has-sub > a { width: calc(100% - 44px); }
  .main-nav .submenu { flex: 1 0 100%; }
}
@media (prefers-reduced-motion: reduce) {
  .btn:hover, .card:hover, .tile:hover, .resource-card:hover { transform: none; }
}

:root { --slate: #526674; }

/* The drawer lives inside the sticky header's stacking context. */
@media (max-width: 980px) {
  .nav-is-open .site-header { z-index: 220; }
}