/* LoongSeek corporate website redesign
   Shape system: 18px surfaces, 12px fields, pill actions. */

:root {
  color-scheme: light dark;
  --bg: #f3f6f4;
  --surface: #fbfcfb;
  --surface-strong: #ffffff;
  --surface-tint: #e9f1ed;
  --ink: #14211c;
  --ink-soft: #2d3c36;
  --muted: #617069;
  --line: rgba(20, 33, 28, 0.14);
  --line-strong: rgba(20, 33, 28, 0.24);
  --accent: #0b8f66;
  --accent-strong: #076c4f;
  --accent-soft: rgba(11, 143, 102, 0.1);
  --shadow: 0 28px 80px rgba(22, 55, 43, 0.12);
  --header-bg: rgba(243, 246, 244, 0.88);
  --radius: 18px;
  --radius-sm: 12px;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --font-sans: "Microsoft YaHei", "PingFang SC", "Noto Sans CJK SC", system-ui, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0e1512;
    --surface: #131d19;
    --surface-strong: #18231f;
    --surface-tint: #1a2923;
    --ink: #edf4f0;
    --ink-soft: #cbd7d1;
    --muted: #9baba3;
    --line: rgba(237, 244, 240, 0.14);
    --line-strong: rgba(237, 244, 240, 0.24);
    --accent: #47bf95;
    --accent-strong: #67d3ad;
    --accent-soft: rgba(71, 191, 149, 0.12);
    --shadow: 0 30px 90px rgba(0, 0, 0, 0.36);
    --header-bg: rgba(14, 21, 18, 0.9);
  }
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  min-width: 320px;
  overflow-x: hidden;
  background: var(--bg);
  color: var(--ink-soft);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}
body.menu-open { overflow: hidden; }
a { color: inherit; text-decoration: none; }
button, input, textarea, select { font: inherit; }
button { color: inherit; }
img { display: block; max-width: 100%; }
ul { list-style: none; }
h1, h2, h3, h4 { color: var(--ink); font-weight: 720; line-height: 1.14; letter-spacing: -0.035em; }
p { text-wrap: pretty; }
::selection { background: var(--accent); color: #f7fffb; }

:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 4px;
  border-radius: 4px;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 1000;
  transform: translateY(-160%);
  padding: 10px 16px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--bg);
  font-weight: 700;
}
.skip-link:focus { transform: none; }

.container { width: min(1280px, calc(100% - 64px)); margin-inline: auto; }
.section { padding: clamp(82px, 10vw, 140px) 0; }
.section--compact { padding: clamp(52px, 7vw, 88px) 0; }
.section--tint { background: var(--surface-tint); }
.section-head { max-width: 760px; margin-bottom: clamp(42px, 6vw, 72px); }
.section-head h2 { font-size: clamp(34px, 4.4vw, 60px); }
.section-head p { max-width: 62ch; margin-top: 18px; color: var(--muted); font-size: 17px; }
.eyebrow {
  display: block;
  margin-bottom: 18px;
  color: var(--accent-strong);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}
.accent { color: var(--accent-strong); }

/* Header */
.header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  border-bottom: 1px solid var(--line);
  background: var(--header-bg);
  -webkit-backdrop-filter: blur(18px) saturate(140%);
  backdrop-filter: blur(18px) saturate(140%);
}
.nav { min-height: 72px; display: flex; align-items: center; justify-content: space-between; gap: 32px; }
.brand { display: inline-flex; align-items: center; gap: 12px; flex: none; color: var(--ink); }
.brand__mark { width: 38px; height: 38px; flex: none; }
.brand__name { display: flex; flex-direction: column; font-size: 17px; font-weight: 800; line-height: 1.05; letter-spacing: 0.02em; }
.brand__sub { margin-top: 6px; color: var(--muted); font-size: 9px; font-weight: 700; letter-spacing: 0.24em; }
.nav__links { display: flex; align-items: center; gap: 4px; }
.nav__links > a:not(.btn) {
  position: relative;
  padding: 10px 15px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
  white-space: nowrap;
  transition: color 220ms var(--ease);
}
.nav__links > a:not(.btn)::after {
  content: "";
  position: absolute;
  right: 15px;
  bottom: 5px;
  left: 15px;
  height: 2px;
  transform: scaleX(0);
  transform-origin: right;
  background: var(--accent);
  transition: transform 260ms var(--ease);
}
.nav__links > a:hover,
.nav__links > a.active { color: var(--ink); }
.nav__links > a:hover::after,
.nav__links > a.active::after { transform: scaleX(1); transform-origin: left; }
.nav__links .btn { margin-left: 14px; }
.nav__toggle {
  display: none;
  width: 46px;
  height: 46px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--surface);
  cursor: pointer;
}
.nav__toggle span { display: block; width: 18px; height: 2px; margin: 4px auto; background: var(--ink); transition: 220ms var(--ease); }
.nav__toggle.open span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav__toggle.open span:nth-child(2) { opacity: 0; }
.nav__toggle.open span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }
.nav-overlay { display: none; }

/* Buttons and text links */
.btn {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 22px;
  border: 1px solid transparent;
  border-radius: 999px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 760;
  line-height: 1;
  white-space: nowrap;
  transition: transform 220ms var(--ease), background 220ms var(--ease), border-color 220ms var(--ease), color 220ms var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(1px) scale(0.98); }
.btn--primary { background: var(--accent-strong); color: #f5fff9; }
.btn--primary:hover { background: var(--accent); }
.btn--secondary { border-color: var(--line-strong); background: transparent; color: var(--ink); }
.btn--secondary:hover { border-color: var(--accent); color: var(--accent-strong); }
.text-link {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-size: 14px;
  font-weight: 750;
}
.text-link::after { content: "↗"; color: var(--accent-strong); transition: transform 220ms var(--ease); }
.text-link:hover::after { transform: translate(3px, -3px); }

/* Home hero */
.home-hero { min-height: min(900px, 100dvh); padding: 112px 0 54px; display: grid; align-items: center; }
.home-hero__grid { display: grid; grid-template-columns: minmax(0, 1.08fr) minmax(420px, 0.92fr); gap: clamp(40px, 7vw, 96px); align-items: center; }
.home-hero__copy { max-width: 720px; }
.home-hero h1 { font-size: clamp(46px, 5.4vw, 76px); }
.home-hero h1 span { display: block; }
.home-hero__lead { max-width: 32em; margin-top: 26px; color: var(--muted); font-size: clamp(17px, 1.55vw, 20px); line-height: 1.8; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 34px; }
.home-hero__visual { position: relative; padding: 0 0 44px 42px; }
.hero-photo {
  overflow: hidden;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  background: var(--surface-tint);
}
.hero-photo img { width: 100%; height: clamp(430px, 53vw, 610px); object-fit: cover; object-position: 56% center; }
.hero-photo--small { position: absolute; left: 0; bottom: 0; width: 43%; border: 8px solid var(--bg); box-shadow: 0 18px 50px rgba(22, 55, 43, 0.18); }
.hero-photo--small img { width: 100%; height: 170px; object-fit: cover; }
.hero-visual__caption { margin: 16px 0 0 48%; color: var(--muted); font-size: 12px; line-height: 1.5; }

.proof-strip { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--surface); }
.proof-grid { display: grid; grid-template-columns: 1.35fr repeat(4, 1fr); align-items: stretch; }
.proof-intro { padding: 32px 28px 32px 0; color: var(--muted); font-size: 14px; }
.proof-item { padding: 26px 24px; border-left: 1px solid var(--line); }
.proof-item strong { display: block; color: var(--ink); font-size: clamp(26px, 2.8vw, 40px); line-height: 1; letter-spacing: -0.04em; }
.proof-item span { display: block; margin-top: 9px; color: var(--muted); font-size: 12px; }

/* Home capability composition */
.capability-grid { display: grid; grid-template-columns: repeat(12, 1fr); gap: 22px; }
.capability {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
}
.capability--equipment { grid-column: span 7; }
.capability--oa { grid-column: span 5; padding: clamp(32px, 5vw, 58px); background: var(--surface-tint); }
.capability--ai { grid-column: 3 / span 10; display: grid; grid-template-columns: 0.86fr 1.14fr; }
.capability__image { overflow: hidden; aspect-ratio: 16 / 8.7; }
.capability__image img { width: 100%; height: 100%; object-fit: cover; transition: transform 700ms var(--ease); }
.capability:hover .capability__image img { transform: scale(1.025); }
.capability__body { padding: clamp(30px, 4vw, 48px); }
.capability h3 { font-size: clamp(26px, 3vw, 40px); }
.capability p { margin: 16px 0 24px; color: var(--muted); }
.capability__index { margin-bottom: 54px; color: var(--accent-strong); font-size: 13px; font-weight: 800; }
.capability--ai .capability__body { display: flex; flex-direction: column; justify-content: center; }
.capability--ai .capability__image { aspect-ratio: auto; min-height: 390px; order: 2; }

.system-story { display: grid; grid-template-columns: minmax(0, 0.78fr) minmax(0, 1.22fr); gap: clamp(46px, 8vw, 120px); align-items: start; }
.system-story__copy { position: sticky; top: 112px; }
.system-story__copy h2 { max-width: 11ch; font-size: clamp(38px, 5vw, 66px); }
.system-story__copy p { max-width: 35ch; margin-top: 22px; color: var(--muted); }
.system-layers { border-top: 1px solid var(--line-strong); }
.system-layer { display: grid; grid-template-columns: 145px 1fr; gap: 28px; padding: 30px 0; border-bottom: 1px solid var(--line); }
.system-layer__name { color: var(--accent-strong); font-size: 14px; font-weight: 800; }
.system-layer h3 { font-size: 23px; letter-spacing: -0.02em; }
.system-layer p { margin-top: 9px; color: var(--muted); font-size: 14px; }

.industry-frame { display: grid; grid-template-columns: 1.2fr 0.8fr; min-height: 560px; overflow: hidden; border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); }
.industry-frame__image img { width: 100%; height: 100%; object-fit: cover; }
.industry-frame__copy { display: flex; flex-direction: column; justify-content: space-between; padding: clamp(34px, 5vw, 68px); }
.industry-frame__copy h2 { font-size: clamp(34px, 4.3vw, 58px); }
.industry-frame__copy p { margin: 18px 0 28px; color: var(--muted); }
.industry-note { padding-top: 28px; border-top: 1px solid var(--line); color: var(--muted); font-size: 13px; }

.delivery-flow { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0; border-top: 1px solid var(--line-strong); }
.delivery-step { min-height: 230px; padding: 30px 28px 26px 0; border-right: 1px solid var(--line); }
.delivery-step + .delivery-step { padding-left: 28px; }
.delivery-step:last-child { border-right: 0; }
.delivery-step__verb { display: block; margin-bottom: 42px; color: var(--accent-strong); font-size: 13px; font-weight: 800; }
.delivery-step h3 { font-size: 23px; }
.delivery-step p { margin-top: 12px; color: var(--muted); font-size: 14px; }

.cta-panel {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 40px;
  align-items: end;
  padding: clamp(38px, 6vw, 74px);
  border-radius: var(--radius);
  background: var(--accent-strong);
  color: rgba(245, 255, 249, 0.78);
}
.cta-panel h2 { max-width: 13ch; color: #f5fff9; font-size: clamp(34px, 4.8vw, 62px); }
.cta-panel p { max-width: 45ch; margin-top: 18px; }
.cta-panel .btn--secondary { border-color: rgba(255,255,255,0.46); color: #f5fff9; }
.cta-panel .btn--secondary:hover { border-color: #f5fff9; color: #f5fff9; }

/* Inner page hero */
.pagehead { padding: 154px 0 88px; border-bottom: 1px solid var(--line); }
.pagehead__inner { display: grid; grid-template-columns: minmax(0, 1fr) minmax(320px, 0.62fr); gap: clamp(40px, 8vw, 120px); align-items: end; }
.crumbs { margin-bottom: 22px; color: var(--muted); font-size: 13px; }
.crumbs a { color: var(--accent-strong); }
.pagehead h1 { max-width: 13ch; font-size: clamp(44px, 6.2vw, 82px); }
.pagehead p { max-width: 38ch; color: var(--muted); font-size: 17px; }

.editorial-split { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr); gap: clamp(44px, 8vw, 110px); align-items: center; }
.editorial-split--reverse .editorial-media { order: -1; }
.editorial-copy h2 { font-size: clamp(34px, 4.4vw, 58px); }
.editorial-copy > p { margin-top: 18px; color: var(--muted); }
.editorial-media { overflow: hidden; border-radius: var(--radius); background: var(--surface-tint); }
.editorial-media img { width: 100%; height: clamp(420px, 52vw, 660px); object-fit: cover; }
.fact-list { margin-top: 30px; border-top: 1px solid var(--line-strong); }
.fact-list li { display: grid; grid-template-columns: 150px 1fr; gap: 22px; padding: 18px 0; border-bottom: 1px solid var(--line); }
.fact-list strong { color: var(--ink); font-size: 14px; }
.fact-list span { color: var(--muted); font-size: 14px; }

/* About */
.values-layout { display: grid; grid-template-columns: 1.18fr 0.82fr; gap: 22px; }
.value-block { padding: clamp(34px, 5vw, 58px); border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.value-block--mission { min-height: 430px; display: flex; flex-direction: column; justify-content: space-between; background: var(--surface-tint); }
.value-block--mission h2 { max-width: 10ch; font-size: clamp(38px, 5vw, 64px); }
.value-stack { display: grid; gap: 22px; }
.value-block h3 { font-size: 26px; }
.value-block p { max-width: 38ch; margin-top: 14px; color: var(--muted); }
.timeline { max-width: 980px; margin-left: auto; }
.timeline-item { display: grid; grid-template-columns: 140px 1fr; gap: 50px; padding: 30px 0; border-top: 1px solid var(--line); }
.timeline-item:last-child { border-bottom: 1px solid var(--line); }
.timeline-item time { color: var(--accent-strong); font-size: 14px; font-weight: 800; }
.timeline-item h3 { font-size: 24px; }
.timeline-item p { margin-top: 8px; color: var(--muted); }
.stats-row { display: grid; grid-template-columns: repeat(4, 1fr); }
.stat { padding: 28px; border-left: 1px solid var(--line); }
.stat:first-child { border-left: 0; padding-left: 0; }
.stat strong { display: block; color: var(--ink); font-size: clamp(32px, 4vw, 54px); line-height: 1; }
.stat span { display: block; margin-top: 12px; color: var(--muted); font-size: 13px; }

/* Products */
.tabs { display: flex; gap: 10px; margin-bottom: 52px; overflow-x: auto; scrollbar-width: none; }
.tabs::-webkit-scrollbar { display: none; }
.tab {
  min-height: 46px;
  flex: none;
  padding: 10px 20px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 14px;
  font-weight: 730;
  white-space: nowrap;
}
.tab:hover { color: var(--ink); border-color: var(--accent); }
.tab.active { border-color: var(--accent-strong); background: var(--accent-strong); color: #f5fff9; }
.tabpanel { display: none; }
.tabpanel.active { display: block; animation: panelIn 420ms var(--ease); }
.product-intro { display: grid; grid-template-columns: 0.72fr 1.28fr; gap: clamp(38px, 8vw, 110px); margin-bottom: 54px; }
.product-intro h2 { font-size: clamp(34px, 4.2vw, 54px); }
.product-intro p { color: var(--muted); }
.product-list { display: grid; grid-template-columns: 1fr 1fr; column-gap: 54px; border-top: 1px solid var(--line-strong); }
.product-item { min-height: 174px; padding: 26px 0; border-bottom: 1px solid var(--line); }
.product-item h3 { font-size: 22px; }
.product-item p { margin-top: 10px; color: var(--muted); font-size: 14px; }
.product-showcase { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 24px; margin-top: 68px; }
.product-showcase__image { overflow: hidden; border-radius: var(--radius); }
.product-showcase__image img { width: 100%; height: 100%; min-height: 440px; object-fit: cover; }
.spec-clusters { display: grid; gap: 14px; }
.spec-cluster { padding: 28px; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); }
.spec-cluster h3 { margin-bottom: 22px; color: var(--accent-strong); font-size: 14px; letter-spacing: 0.06em; }
.spec-pair { display: flex; justify-content: space-between; gap: 20px; padding: 10px 0; }
.spec-pair + .spec-pair { border-top: 1px solid var(--line); }
.spec-pair b { color: var(--ink); font-size: 14px; }
.spec-pair span { color: var(--muted); font-size: 14px; text-align: right; }
.advantage-grid { display: grid; grid-template-columns: 1.2fr 0.8fr; gap: 22px; margin-top: 68px; }
.advantage-copy { padding: clamp(34px, 5vw, 60px); border-radius: var(--radius); background: var(--surface-tint); }
.advantage-copy h3 { font-size: clamp(28px, 3.5vw, 42px); }
.advantage-copy ul { margin-top: 24px; }
.advantage-copy li { padding: 14px 0; border-top: 1px solid var(--line); color: var(--muted); }
.advantage-copy li strong { display: block; color: var(--ink); }
.advantage-image { overflow: hidden; border-radius: var(--radius); }
.advantage-image img { width: 100%; height: 100%; min-height: 480px; object-fit: cover; }

/* Contact */
.contact-grid { display: grid; grid-template-columns: 0.85fr 1.15fr; gap: clamp(42px, 8vw, 110px); align-items: start; }
.contact-details h2 { font-size: clamp(34px, 4vw, 52px); }
.contact-details > p { margin-top: 16px; color: var(--muted); }
.contact-list { margin-top: 36px; border-top: 1px solid var(--line-strong); }
.contact-list li { padding: 20px 0; border-bottom: 1px solid var(--line); }
.contact-list span { display: block; color: var(--muted); font-size: 12px; }
.contact-list strong { display: block; margin-top: 3px; color: var(--ink); font-size: 16px; letter-spacing: -0.01em; }
.contact-photo { overflow: hidden; margin-top: 34px; border-radius: var(--radius); }
.contact-photo img { width: 100%; aspect-ratio: 16 / 10; object-fit: cover; }
.form { padding: clamp(28px, 5vw, 48px); border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); box-shadow: var(--shadow); }
.form h2 { margin-bottom: 30px; font-size: clamp(28px, 3vw, 38px); }
.field--row { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.field { margin-bottom: 20px; }
.field label { display: block; margin-bottom: 8px; color: var(--ink); font-size: 13px; font-weight: 720; }
.field input,
.field textarea,
.field select {
  width: 100%;
  min-height: 52px;
  padding: 13px 15px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  outline: 0;
  background: var(--bg);
  color: var(--ink);
  font-size: 15px;
  transition: border-color 180ms var(--ease), box-shadow 180ms var(--ease), background 180ms var(--ease);
}
.field textarea { min-height: 150px; resize: vertical; }
.field input::placeholder,
.field textarea::placeholder { color: var(--muted); opacity: 0.84; }
.field input:focus,
.field textarea:focus,
.field select:focus { border-color: var(--accent); background: var(--surface-strong); box-shadow: 0 0 0 4px var(--accent-soft); }
.form__note { margin-top: 13px; color: var(--muted); font-size: 12px; }
.form__msg { display: none; margin-bottom: 22px; padding: 15px 17px; border: 1px solid var(--accent); border-radius: var(--radius-sm); background: var(--accent-soft); color: var(--ink); font-size: 14px; }
.form__msg.show { display: block; }

/* Footer */
.footer { padding: 78px 0 28px; border-top: 1px solid var(--line); background: var(--surface); }
.footer__top { display: grid; grid-template-columns: 1.35fr 0.75fr 0.75fr 1fr; gap: 46px; padding-bottom: 52px; }
.footer__brand p { max-width: 360px; margin-top: 20px; color: var(--muted); font-size: 13px; }
.footer__col h3 { margin-bottom: 18px; font-size: 14px; letter-spacing: 0; }
.footer__col a { display: block; width: fit-content; padding: 5px 0; color: var(--muted); font-size: 13px; }
.footer__col a:hover { color: var(--accent-strong); }
.footer__contact li { margin-bottom: 12px; color: var(--muted); font-size: 13px; overflow-wrap: anywhere; }
.beian { padding: 22px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.beian__wrap { display: flex; flex-wrap: wrap; justify-content: center; gap: 8px 22px; color: var(--muted); font-size: 12px; text-align: center; }
.beian__wrap a:hover { color: var(--accent-strong); }
.copyright { padding-top: 24px; color: var(--muted); font-size: 12px; text-align: center; }

/* Motion */
@keyframes panelIn { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: none; } }
.js .reveal { opacity: 0; transform: translateY(24px); transition: opacity 650ms var(--ease), transform 650ms var(--ease); }
.js .reveal.in { opacity: 1; transform: none; }
.js .reveal[data-delay="1"] { transition-delay: 70ms; }
.js .reveal[data-delay="2"] { transition-delay: 140ms; }
.js .reveal[data-delay="3"] { transition-delay: 210ms; }

@media (prefers-reduced-transparency: reduce) {
  .header { background: var(--bg); -webkit-backdrop-filter: none; backdrop-filter: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; transition-duration: 0.01ms !important; scroll-behavior: auto !important; }
  .js .reveal { opacity: 1; transform: none; }
}

/* Responsive */
@media (max-width: 1080px) {
  .home-hero { min-height: auto; padding-top: 124px; }
  .home-hero__grid { grid-template-columns: 1fr 0.82fr; gap: 44px; }
  .home-hero h1 { font-size: clamp(44px, 5.8vw, 62px); }
  .proof-grid { grid-template-columns: repeat(4, 1fr); }
  .proof-intro { grid-column: 1 / -1; padding: 22px 0; border-bottom: 1px solid var(--line); }
  .proof-item:first-of-type { border-left: 0; }
  .capability--ai { grid-column: 1 / -1; }
  .footer__top { grid-template-columns: 1.4fr 1fr 1fr; }
  .footer__top .footer__col:last-child { grid-column: 2 / -1; }
}

@media (max-width: 820px) {
  .container { width: min(100% - 36px, 720px); }
  .header { background: var(--bg); -webkit-backdrop-filter: none; backdrop-filter: none; }
  .nav { min-height: 66px; }
  .brand__mark { width: 36px; height: 36px; }
  .nav__toggle { display: block; }
  .nav__links {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    z-index: 102;
    width: min(86vw, 360px);
    display: flex;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 2px;
    padding: 92px 24px 30px;
    transform: translateX(105%);
    background: var(--surface-strong);
    box-shadow: -24px 0 70px rgba(0,0,0,0.22);
    transition: transform 320ms var(--ease);
  }
  .nav__links.open { transform: none; }
  .nav__links > a:not(.btn) { padding: 15px 4px; border-bottom: 1px solid var(--line); color: var(--ink); font-size: 18px; }
  .nav__links > a:not(.btn)::after { display: none; }
  .nav__links .btn { width: 100%; margin: 22px 0 0; }
  .nav-overlay { position: fixed; inset: 0; z-index: 101; display: block; visibility: hidden; opacity: 0; background: rgba(10,18,14,0.5); transition: opacity 220ms var(--ease), visibility 220ms var(--ease); }
  .nav-overlay.open { visibility: visible; opacity: 1; }
  .nav__toggle { position: relative; z-index: 103; }

  .home-hero { padding: 104px 0 46px; }
  .home-hero__grid { grid-template-columns: 1fr; gap: 44px; }
  .home-hero__copy { max-width: none; }
  .home-hero h1 { font-size: clamp(40px, 10vw, 58px); }
  .home-hero__lead { max-width: 38em; }
  .home-hero__visual { padding-left: 24px; }
  .hero-photo img { height: min(72vw, 520px); }
  .hero-photo--small { width: 38%; border-width: 6px; }
  .hero-photo--small img { height: 140px; }
  .proof-grid { grid-template-columns: repeat(2, 1fr); }
  .proof-item:nth-of-type(3) { border-left: 0; border-top: 1px solid var(--line); }
  .proof-item:nth-of-type(4) { border-top: 1px solid var(--line); }

  .capability--equipment, .capability--oa, .capability--ai { grid-column: 1 / -1; }
  .capability--ai { grid-template-columns: 1fr; }
  .capability--ai .capability__image { min-height: 330px; order: 0; }
  .capability__index { margin-bottom: 30px; }
  .system-story { grid-template-columns: 1fr; }
  .system-story__copy { position: static; }
  .system-story__copy h2 { max-width: 14ch; }
  .industry-frame { grid-template-columns: 1fr; }
  .industry-frame__image img { height: 430px; }
  .delivery-flow { grid-template-columns: repeat(2, 1fr); }
  .delivery-step:nth-child(2) { border-right: 0; }
  .delivery-step:nth-child(n+3) { border-top: 1px solid var(--line); }
  .delivery-step:nth-child(3) { padding-left: 0; }
  .cta-panel { grid-template-columns: 1fr; align-items: start; }

  .pagehead { padding: 128px 0 70px; }
  .pagehead__inner { grid-template-columns: 1fr; gap: 24px; }
  .pagehead p { max-width: 48ch; }
  .editorial-split { grid-template-columns: 1fr; }
  .editorial-split--reverse .editorial-media { order: 0; }
  .editorial-media img { height: min(92vw, 560px); }
  .values-layout { grid-template-columns: 1fr; }
  .value-block--mission { min-height: 340px; }
  .stats-row { grid-template-columns: repeat(2, 1fr); }
  .stat:nth-child(3) { border-left: 0; border-top: 1px solid var(--line); padding-left: 0; }
  .stat:nth-child(4) { border-top: 1px solid var(--line); }
  .product-intro { grid-template-columns: 1fr; gap: 18px; }
  .product-showcase, .advantage-grid { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer__top { grid-template-columns: 1fr 1fr; }
  .footer__brand { grid-column: 1 / -1; }
  .footer__top .footer__col:last-child { grid-column: 1 / -1; }
}

@media (max-width: 560px) {
  .container { width: calc(100% - 32px); }
  .section { padding: 72px 0; }
  .section-head { margin-bottom: 38px; }
  .section-head h2 { font-size: 34px; }
  .home-hero h1 { font-size: clamp(38px, 11.3vw, 52px); }
  .home-hero__lead { margin-top: 20px; font-size: 16px; }
  .hero-actions { flex-direction: column; align-items: stretch; margin-top: 28px; }
  .hero-actions .btn { width: 100%; }
  .home-hero__visual { padding: 0 0 32px 12px; }
  .hero-photo img { height: 240px; }
  .hero-photo--small { display: none; }
  .hero-visual__caption { margin: 12px 0 0; }
  .proof-item { padding: 22px 16px; }
  .proof-item strong { font-size: 30px; }
  .capability__body, .capability--oa { padding: 28px 24px; }
  .capability__image { aspect-ratio: 4 / 3; }
  .capability--ai .capability__image { min-height: 260px; }
  .system-layer { grid-template-columns: 1fr; gap: 8px; }
  .industry-frame__image img { height: 320px; }
  .delivery-flow { grid-template-columns: 1fr; }
  .delivery-step, .delivery-step + .delivery-step { min-height: auto; padding: 24px 0; border-right: 0; border-top: 1px solid var(--line); }
  .delivery-step:first-child { border-top: 0; }
  .delivery-step__verb { margin-bottom: 20px; }
  .cta-panel { padding: 34px 24px; }
  .cta-panel h2 { font-size: 36px; }

  .pagehead { padding: 112px 0 58px; }
  .pagehead h1 { font-size: 45px; }
  .fact-list li { grid-template-columns: 1fr; gap: 4px; }
  .timeline-item { grid-template-columns: 1fr; gap: 8px; }
  .stats-row { grid-template-columns: 1fr 1fr; }
  .stat { padding: 22px 14px; }
  .product-list { grid-template-columns: 1fr; }
  .product-showcase__image img { min-height: 320px; }
  .field--row { grid-template-columns: 1fr; gap: 0; }
  .form { padding: 26px 20px; }
  .footer__top { grid-template-columns: 1fr; }
  .footer__brand, .footer__top .footer__col:last-child { grid-column: auto; }
  .beian__sep { display: none; }
}