:root {
  color-scheme: dark;
  --ink: #100f0d;
  --surface: #171410;
  --text: #f7f0e6;
  --muted: #c3b9aa;
  --quiet: #a59786;
  --gold: #e8b870;
  --rule: #3a3126;
  --sans: system-ui, "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --zh: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --mono: "Cascadia Mono", "SFMono-Regular", Consolas, monospace;
  font-family: var(--sans);
  font-synthesis: none;
  scroll-behavior: smooth;
}

*, *::before, *::after { box-sizing: border-box; }
body { margin: 0; background: var(--ink); color: var(--text); }
h1, h2, p, ul, ol { margin: 0; }
a { color: inherit; text-decoration: none; }
a:focus-visible { outline: 2px solid var(--gold); outline-offset: 4px; }
img { display: block; max-width: 100%; }
section[id] { scroll-margin-top: 20px; }
::selection { background: var(--gold); color: var(--ink); }
.translation { display: block; color: var(--muted); font: 400 .85em/1.55 var(--zh); }
.copy-pair { display: grid; gap: 6px; }

.shell { width: min(1200px, calc(100% - 104px)); margin-inline: auto; }
.skip-link {
  position: absolute;
  z-index: 5;
  top: 10px;
  left: 10px;
  padding: 12px 16px;
  transform: translateY(-150%);
  color: var(--ink);
  background: var(--gold);
}
.skip-link:focus { transform: none; }
.skip-link .translation { color: inherit; }

.site-header { border-bottom: 1px solid #2e261d; background: #100e0c; }
.header-inner, .site-header nav, .brand {
  display: flex;
  align-items: center;
}
.header-inner { justify-content: space-between; min-height: 74px; gap: 20px; }
.brand { flex: 0 0 auto; padding-block: 10px; }
.brand img { width: 174px; height: auto; }
.site-header nav { gap: clamp(18px, 3.2vw, 45px); }
.site-header nav a { padding-block: 10px; color: var(--text); font-size: 15px; font-weight: 650; line-height: 1.35; }
.site-header nav .translation { margin-top: 2px; }
.site-header nav a:hover { color: var(--gold); }
.site-header nav .nav-contact { color: var(--gold); }

.hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  background: #16110b;
  border-bottom: 1px solid var(--rule);
}
.hero-image, .hero::after {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: -1;
}
.hero-image { object-fit: cover; object-position: center 54%; }
.hero::after {
  content: "";
  background:
    linear-gradient(90deg, #100d09 2%, #110e0be8 31%, #110e0b6b 66%, #110e0b0a 100%),
    linear-gradient(0deg, #100d09 0%, transparent 34%);
}
.hero-inner { min-height: 621px; display: grid; align-items: center; padding-block: 76px 92px; }
.hero-copy { width: min(840px, 100%); }
.eyebrow {
  color: var(--gold);
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1.6;
  letter-spacing: .15em;
  font-weight: 600;
}
.eyebrow > span:first-child:not(.signal) { margin-right: 5px; }
.hero .eyebrow { display: flex; align-items: center; gap: 10px; }
.signal { display: inline-block; width: 7px; height: 7px; border-radius: 50%; background: var(--gold); flex: 0 0 7px; }
.hero h1 {
  margin-block: 18px 12px;
  font-size: clamp(47px, 6.2vw, 90px);
  font-weight: 750;
  line-height: 1.04;
  letter-spacing: -.065em;
}
.hero h1 span { color: var(--gold); }
.hero-subtitle { margin-bottom: 22px; color: #f0d3aa; font-size: clamp(17px, 2vw, 26px); }
.hero-description { max-width: 530px; color: #eee3d4; font-size: 17px; line-height: 1.65; }
.hero-actions, .contact-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 20px 24px; }
.hero-actions { margin-top: 26px; }
.button, .text-link { display: inline-flex; align-items: center; gap: 11px; font-weight: 650; font-size: 15px; line-height: 1.4; }
.button { justify-content: center; min-height: 50px; padding: 12px 19px; border-radius: 5px; }
.button-primary { color: #1d1408; background: var(--gold); }
.button-primary:hover { background: #f7cc8d; }
.button .translation { color: inherit; }
.text-link { color: var(--gold); padding-block: 7px; }
.text-link:hover { text-decoration: underline; text-underline-offset: 4px; }
.hero-index {
  position: absolute;
  right: max(52px, calc((100% - 1200px) / 2));
  bottom: 28px;
  display: grid;
  gap: 4px;
  text-align: right;
  color: #d5c6b3;
  font-size: 11px;
  letter-spacing: .1em;
}
.hero-index span:first-child { color: var(--gold); font-family: var(--mono); }

.section { padding-block: 86px; }
.section h2, .contact-section h2 { font-size: clamp(30px, 4vw, 50px); line-height: 1.22; letter-spacing: -.04em; }
.section-subtitle { margin-top: 8px; color: #ddc3a0; font-size: clamp(15px, 1.45vw, 19px); }
.section-intro { display: grid; grid-template-columns: 1.5fr 1fr; gap: 25px; align-items: end; margin-bottom: 34px; }
.section-intro h2, .contact-section h2 { margin-top: 10px; }
.section-intro > .copy-pair { max-width: 380px; justify-self: end; color: var(--text); font-size: 15px; line-height: 1.65; }

.product-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  background: var(--rule);
  border: 1px solid var(--rule);
  gap: 1px;
}
.product {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  min-height: 225px;
  padding: 24px;
  background: var(--surface);
}
.product:hover, .product:focus-visible { background: #241d15; }
.product:focus-visible { outline-offset: -3px; }
.product-icon { display: grid; width: 48px; height: 48px; place-items: center; color: var(--gold); }
.product-icon svg { width: 42px; fill: none; stroke: currentColor; stroke-width: 1.55; stroke-linecap: round; stroke-linejoin: round; }
.product-arrow { position: absolute; top: 27px; right: 23px; color: var(--gold); font-size: 19px; }
.product-name { margin-top: 18px; font-weight: 700; font-size: 23px; line-height: 1.2; }
.product-zh { margin-top: 5px; color: var(--gold); font-size: 13px; }
.product-description { margin-block: 12px 7px; color: var(--text); font-size: 14px; line-height: 1.55; }
.product > .translation:last-child { font-size: 12px; }
.product-extra, .story-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px 24px;
  padding-top: 19px;
  font-size: 14px;
}

.story-section { background: #17130f; border-block: 1px solid #292219; }
.timeline {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  list-style: none;
  padding: 0;
  border-top: 1px solid #685138;
}
.timeline li { position: relative; display: grid; align-content: start; gap: 8px; padding: 23px 16px 24px 0; }
.timeline li::before {
  content: "";
  position: absolute;
  top: -4px;
  left: 0;
  width: 7px;
  height: 7px;
  background: var(--gold);
  border-radius: 50%;
}
.timeline time { font-family: var(--mono); font-size: clamp(29px, 4vw, 47px); color: var(--gold); letter-spacing: -.06em; }
.timeline li span:not(.translation) { color: var(--text); font-size: 15px; line-height: 1.45; }
.timeline .translation { font-size: 13px; }
.story-footer { border-top: 1px solid var(--rule); }

.engineering-panel {
  display: grid;
  grid-template-columns: 1.6fr 1fr;
  margin-top: 16px;
  border: 1px solid var(--rule);
  background: #18140f;
}
.engineering-copy { padding: clamp(24px, 4vw, 54px); }
.status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 10px;
  border: 1px solid #5e492d;
  border-radius: 4px;
  color: #f1ce9b;
  font-size: 12px;
}
.engineering-copy h2 { margin-top: 16px; font-size: clamp(29px, 3.7vw, 49px); text-wrap: balance; }
.engineering-copy .copy-pair { max-width: 490px; margin-top: 16px; font-size: 15px; line-height: 1.65; }
.project-directions { display: flex; flex-wrap: wrap; gap: 8px; padding: 0; margin-block: 22px 15px; list-style: none; }
.project-directions li { padding: 7px 9px; border: 1px solid var(--rule); color: #e4d4bd; font-size: 13px; }
.engineering-art {
  display: grid;
  align-content: center;
  justify-items: center;
  min-height: 275px;
  padding: 25px;
  color: var(--gold);
  border-left: 1px solid var(--rule);
  background: radial-gradient(ellipse at center, #382918, #1a1510 68%);
}
.engineering-art svg { display: block; width: min(100%, 320px); }
.engineering-art span { font-family: var(--mono); font-size: 13px; letter-spacing: .24em; }

.contact-section { border-top: 1px solid var(--rule); background: #1b1610; padding-block: 53px; }
.contact-inner, .footer-inner { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 20px 28px; }
.contact-section address { margin-top: 12px; font-style: normal; font-size: 15px; line-height: 1.7; }
.site-footer { border-top: 1px solid var(--rule); color: var(--quiet); font-size: 13px; }
.footer-inner { padding-block: 25px; }
.site-footer a { font-family: var(--mono); letter-spacing: .08em; }
.site-footer a:hover { color: var(--gold); }

@media (max-width: 900px) {
  .shell { width: calc(100% - 56px); }
  .hero-index { right: 28px; }
  .hero-inner { min-height: 545px; }
  .section { padding-block: 65px; }
  .product { padding: 20px; }
}

@media (max-width: 650px) {
  .shell { width: calc(100% - 40px); }
  .header-inner { display: block; padding-block: 9px 4px; }
  .brand { display: inline-flex; }
  .brand img { width: 145px; }
  .site-header nav { justify-content: space-between; gap: 8px 12px; margin-top: 3px; }
  .site-header nav a { font-size: clamp(12px, 3.3vw, 14px); }
  .hero-inner { min-height: 550px; padding-block: 115px 82px; }
  .hero-image { object-position: 64% center; }
  .hero::after { background: linear-gradient(0deg, #100d09 1%, #100d09e0 23%, #100d0988 75%, #100d0922 100%); }
  .hero h1 { font-size: clamp(29px, 8.4vw, 52px); margin-block: 16px 11px; }
  .hero-subtitle { margin-bottom: 15px; }
  .hero-description { max-width: 420px; font-size: 15px; }
  .hero-actions { gap: 12px 16px; margin-top: 22px; }
  .hero-actions .button, .hero-actions .text-link { font-size: 13px; }
  .hero-actions .button { padding-inline: 12px; }
  .hero-index { right: 20px; bottom: 20px; }
  .section { padding-block: 53px; }
  .section-intro { grid-template-columns: 1fr; gap: 12px; margin-bottom: 23px; }
  .section-intro > .copy-pair { max-width: 480px; justify-self: start; }
  .product-grid, .timeline { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .product { min-height: 195px; padding: 15px; }
  .product-arrow { top: 21px; right: 16px; }
  .product-name { margin-top: 11px; font-size: clamp(18px, 4.75vw, 22px); }
  .product-description { margin-top: 10px; }
  .timeline { border-top: 0; }
  .timeline li { border-top: 1px solid #685138; padding-block: 16px; }
  .timeline li span:not(.translation) { font-size: 14px; }
  .engineering-panel { grid-template-columns: 1fr; }
  .engineering-art { min-height: 185px; border-left: 0; border-top: 1px solid var(--rule); }
  .engineering-art svg { width: min(100%, 210px); }
  .contact-section { padding-block: 41px; }
  .footer-inner { gap: 12px 24px; }
}

@media (prefers-reduced-motion: reduce) {
  :root { scroll-behavior: auto; }
}