:root {
  --ink: #102b2b;
  --ink-deep: #071a1b;
  --copper: #c68d54;
  --paper: #f4f1eb;
  --line: rgba(16, 43, 43, 0.18);
  --muted: #667271;
  --sans: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", sans-serif;
  --serif: "Songti SC", "STSong", "Noto Serif CJK SC", serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }

.site-header {
  position: fixed;
  z-index: 20;
  top: 0;
  left: 0;
  width: 100%;
  height: 88px;
  padding: 0 5vw;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: #fff;
  border-bottom: 1px solid rgba(255,255,255,.16);
  transition: background .35s, height .35s, color .35s;
}
.site-header.scrolled {
  height: 72px;
  color: var(--ink);
  background: rgba(244,241,235,.94);
  backdrop-filter: blur(16px);
  border-color: var(--line);
}
.brand { display: flex; align-items: center; gap: 12px; }
.brand-mark {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  color: #fff;
  background: var(--copper);
  font: 700 24px/1 Georgia, serif;
}
.brand strong, .footer-brand strong { display: block; letter-spacing: .16em; font-size: 17px; }
.brand small, .footer-brand small { display: block; margin-top: 3px; font-size: 7px; letter-spacing: .22em; opacity: .72; }
.site-nav { display: flex; gap: 40px; font-size: 14px; }
.site-nav a { position: relative; }
.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -8px;
  width: 100%;
  height: 1px;
  background: currentColor;
  transform: scaleX(0);
  transform-origin: right;
  transition: transform .25s;
}
.site-nav a:hover::after { transform: scaleX(1); transform-origin: left; }
.menu-button { display: none; }

.hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  align-items: center;
  overflow: hidden;
  color: #fff;
}
.hero-media {
  position: absolute;
  inset: 0;
  background: url("./assets/hangzhou-hero.png") center center/cover no-repeat;
  animation: heroScale 14s ease-out both;
}
.hero-shade {
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, rgba(3,16,20,.93) 0%, rgba(4,20,25,.76) 38%, rgba(4,17,22,.1) 73%),
              linear-gradient(0deg, rgba(3,15,17,.46), transparent 45%);
}
.hero-content {
  position: relative;
  z-index: 2;
  width: min(650px, 82vw);
  margin-left: 9vw;
  padding-top: 70px;
}
.eyebrow, .kicker { color: var(--copper); font-size: 11px; letter-spacing: .28em; }
.hero h1 {
  margin: 26px 0 24px;
  font: 500 clamp(46px, 5.1vw, 80px)/1.18 var(--serif);
  letter-spacing: .04em;
}
.hero-copy { max-width: 520px; margin: 0; color: rgba(255,255,255,.72); font-size: 17px; line-height: 1.9; }
.hero-actions { display: flex; align-items: center; gap: 38px; margin-top: 42px; }
.button { display: inline-flex; min-width: 146px; height: 50px; align-items: center; justify-content: center; font-size: 14px; }
.button-primary { color: #fff; background: var(--copper); transition: transform .25s, background .25s; }
.button-primary:hover { background: #b87c43; transform: translateY(-2px); }
.text-link { font-size: 14px; border-bottom: 1px solid rgba(255,255,255,.35); padding: 10px 0; }
.text-link span { margin-left: 12px; }
.scroll-hint {
  position: absolute;
  z-index: 2;
  right: 5vw;
  bottom: 0;
  height: 160px;
  display: flex;
  align-items: center;
  gap: 18px;
  writing-mode: vertical-rl;
  font-size: 8px;
  letter-spacing: .3em;
  color: rgba(255,255,255,.58);
}
.scroll-hint i { display: block; width: 1px; height: 70px; background: rgba(255,255,255,.5); animation: scrollLine 2s infinite; }

.section { padding: 120px 8vw; }
.section-label { display: flex; align-items: center; gap: 16px; color: var(--muted); font-size: 12px; letter-spacing: .18em; }
.section-label span { color: var(--copper); }
.section-label p { margin: 0; }
.section-label::after { content: ""; width: 70px; height: 1px; background: var(--line); }
.intro-heading { max-width: 830px; margin: 62px 0 70px 20vw; }
.intro-heading h2, .about h2, .contact h2, .approach h2 {
  margin: 18px 0 22px;
  font: 500 clamp(34px, 4.2vw, 60px)/1.28 var(--serif);
  letter-spacing: .03em;
}
.intro-heading > p:last-child { max-width: 670px; color: var(--muted); line-height: 2; }
.service-list { border-top: 1px solid var(--line); }
.service-item {
  min-height: 180px;
  display: grid;
  grid-template-columns: 70px 110px 1fr 180px;
  align-items: center;
  gap: 20px;
  border-bottom: 1px solid var(--line);
  transition: padding .3s, background .3s;
}
.service-item:hover { padding: 0 22px; background: rgba(255,255,255,.42); }
.service-number, .service-en { color: var(--copper); font-size: 10px; letter-spacing: .2em; }
.service-icon svg { width: 54px; fill: none; stroke: var(--ink); stroke-width: 1.3; }
.service-item h3 { margin: 0 0 14px; font: 500 24px var(--serif); }
.service-item p { max-width: 620px; margin: 0; color: var(--muted); font-size: 14px; line-height: 1.8; }
.service-en { text-align: right; color: var(--muted); }

.approach { color: #fff; background: var(--ink-deep); }
.approach-inner { padding: 120px 8vw; background-image: radial-gradient(circle at 70% 30%, rgba(198,141,84,.12), transparent 28%); }
.section-label.light { color: rgba(255,255,255,.5); }
.section-label.light::after { background: rgba(255,255,255,.16); }
.approach-title { margin: 60px 0 70px 20vw; }
.steps { margin: 0 0 0 20vw; padding: 0; list-style: none; border-top: 1px solid rgba(255,255,255,.16); }
.steps li {
  display: grid;
  grid-template-columns: 85px 1fr;
  padding: 32px 0;
  border-bottom: 1px solid rgba(255,255,255,.16);
}
.steps li > span { color: var(--copper); font-size: 11px; }
.steps h3 { margin: 0 0 10px; font: 400 22px var(--serif); }
.steps p { margin: 0; color: rgba(255,255,255,.55); font-size: 14px; }

.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10vw; margin-top: 70px; }
.about-copy h2 { margin-top: 20px; }
.about-detail > p { margin: 0 0 22px; color: var(--muted); line-height: 2; }
.about-detail dl { margin: 44px 0 0; border-top: 1px solid var(--line); }
.about-detail dl div { display: grid; grid-template-columns: 100px 1fr; padding: 18px 0; border-bottom: 1px solid var(--line); }
.about-detail dt { color: var(--muted); font-size: 12px; }
.about-detail dd { margin: 0; font-size: 13px; }

.contact { padding: 110px 8vw; color: #fff; background: var(--copper); }
.contact-inner { max-width: 1050px; margin: auto; }
.contact .kicker { color: rgba(255,255,255,.62); }
.contact h2 { margin: 20px 0 60px; font-size: clamp(40px, 5vw, 68px); }
.contact-details { display: grid; grid-template-columns: 1fr 1fr; gap: 50px; border-top: 1px solid rgba(255,255,255,.3); padding-top: 28px; }
.contact-details span { font-size: 11px; letter-spacing: .18em; opacity: .65; }
.contact-details p { margin: 12px 0 0; line-height: 1.8; }

footer {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  padding: 54px 8vw;
  color: rgba(255,255,255,.72);
  background: #071617;
}
.footer-brand { display: flex; align-items: center; gap: 12px; color: #fff; }
.footer-meta { text-align: right; font-size: 11px; line-height: 1.9; }
.footer-meta p { margin: 0; }
.record a:hover { color: #fff; }

.reveal { opacity: 0; transform: translateY(28px); transition: opacity .75s ease, transform .75s ease; }
.reveal.visible { opacity: 1; transform: none; }
@keyframes heroScale { from { transform: scale(1.07); } to { transform: scale(1); } }
@keyframes scrollLine { 0%, 100% { transform: scaleY(.3); transform-origin: top; } 50% { transform: scaleY(1); transform-origin: top; } }

@media (max-width: 760px) {
  .site-header { height: 72px; padding: 0 22px; }
  .site-nav {
    position: fixed;
    inset: 72px 0 auto;
    display: grid;
    padding: 30px 24px 38px;
    gap: 24px;
    color: var(--ink);
    background: var(--paper);
    transform: translateY(-130%);
    transition: transform .35s;
  }
  .site-nav.open { transform: none; }
  .menu-button {
    display: grid;
    width: 42px;
    height: 42px;
    padding: 12px;
    border: 0;
    background: transparent;
  }
  .menu-button span { display: block; width: 18px; height: 1px; background: currentColor; }
  .hero-content { width: auto; margin: 0 24px; padding-top: 60px; }
  .hero-shade { background: linear-gradient(90deg, rgba(3,16,20,.92), rgba(3,16,20,.42)), linear-gradient(0deg, rgba(3,15,17,.55), transparent); }
  .hero h1 { font-size: 38px; letter-spacing: .02em; }
  .hero-copy { font-size: 14px; }
  .scroll-hint { display: none; }
  .section, .approach-inner { padding: 84px 24px; }
  .intro-heading, .approach-title, .steps { margin-left: 0; }
  .intro-heading { margin-top: 46px; }
  .service-item { grid-template-columns: 42px 1fr; padding: 30px 0; }
  .service-item:hover { padding: 30px 10px; }
  .service-icon { display: none; }
  .service-en { display: none; }
  .service-item h3 { font-size: 21px; }
  .about-grid { grid-template-columns: 1fr; gap: 32px; }
  .contact { padding: 84px 24px; }
  .contact-details { grid-template-columns: 1fr; gap: 30px; }
  footer { align-items: flex-start; flex-direction: column; gap: 34px; padding: 44px 24px; }
  .footer-meta { text-align: left; }
}

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