/* ============ 太仓智信 · 数字粒子企业官网 ============ */

@font-face {
  font-family: 'Newsreader';
  src: url('/assets/fonts/newsreader-latin.woff2') format('woff2');
  font-weight: 200 800;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Noto Serif SC';
  src: url('/assets/fonts/notoserifsc-subset.woff2') format('woff2');
  font-weight: 200 900;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Inter';
  src: url('/assets/fonts/inter-latin.woff2') format('woff2');
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}
@font-face {
  font-family: 'Noto Sans SC';
  src: url('/assets/fonts/notosanssc-subset.woff2') format('woff2');
  font-weight: 100 900;
  font-style: normal;
  font-display: swap;
}

:root {
  --black: #0b0a08;
  --board: #fdfdfb;
  --ink: #161310;
  --muted: #6d675f;
  --faint: #98918a;
  --hairline: #e6e2db;
  --orange: #ee5a1c;
  --orange-deep: #c74a10;
  --dark-band: #0e0c0a;
  --dark-hairline: #2c2823;
  --dark-muted: #b6afa7;
  --serif: 'Newsreader', 'Noto Serif SC', 'Songti SC', serif;
  --sans: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --pad: clamp(20px, 4vw, 56px);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  background: var(--black);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.75;
  padding: clamp(10px, 2.4vw, 40px);
  -webkit-font-smoothing: antialiased;
}

.sr-only {
  position: absolute; width: 1px; height: 1px;
  clip-path: inset(50%); overflow: hidden; white-space: nowrap;
}

.margin-deco {
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
}
.margin-deco svg { width: 100%; height: 100%; display: block; }

.board {
  position: relative; z-index: 1;
  max-width: 1600px; margin: 0 auto;
  background: var(--board);
  box-shadow: 0 0 0 1px rgba(255,255,255,.06), 0 40px 120px rgba(0,0,0,.55);
}

.caps {
  font-family: var(--sans);
  font-size: 11px;
  letter-spacing: .18em;
  text-transform: uppercase;
  color: var(--faint);
  line-height: 1.9;
}

.eyebrow {
  font-size: 12px;
  letter-spacing: .22em;
  text-transform: uppercase;
  color: var(--muted);
  font-weight: 500;
}

.arr { display: inline-block; transition: transform .3s ease; }
a:hover .arr { transform: translateX(5px); }

.flower { width: 44px; height: 44px; color: var(--orange); flex: none; }
.spin { animation: spin 26s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* ---------- nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px;
  padding: 18px var(--pad);
  background: rgba(253,253,251,.92);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--hairline);
  transition: padding .3s ease, box-shadow .3s ease;
}
.nav.scrolled { padding-top: 12px; padding-bottom: 12px; box-shadow: 0 8px 30px rgba(20,15,10,.08); }

.brand { display: flex; align-items: baseline; gap: 12px; text-decoration: none; color: var(--ink); }
.brand-cn { font-family: var(--serif); font-size: 24px; font-weight: 600; letter-spacing: .04em; }
.brand-en { font-size: 11px; letter-spacing: .22em; text-transform: uppercase; color: var(--faint); }

.nav-links { display: flex; align-items: center; gap: clamp(20px, 3vw, 44px); }
.nav-links a {
  text-decoration: none; color: var(--ink);
  font-size: 13px; letter-spacing: .14em; font-weight: 500;
  transition: color .25s ease;
}
.nav-links a:hover { color: var(--orange); }
.nav-cta {
  background: var(--orange); color: #fff !important;
  padding: 10px 22px; border-radius: 999px;
  letter-spacing: .12em !important;
  transition: background .25s ease, transform .25s ease !important;
}
.nav-cta:hover { background: var(--orange-deep); transform: translateY(-1px); }

.nav-toggle {
  display: none;
  background: none; border: 0; cursor: pointer;
  width: 40px; height: 40px;
  flex-direction: column; align-items: center; justify-content: center; gap: 7px;
}
.nav-toggle span { display: block; width: 22px; height: 2px; background: var(--ink); transition: transform .3s ease; }
.nav-toggle[aria-expanded="true"] span:first-child { transform: translateY(4.5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:last-child { transform: translateY(-4.5px) rotate(-45deg); }

/* ---------- hero ---------- */
.hero {
  display: grid;
  grid-template-columns: 1.25fr 1fr;
  height: clamp(560px, calc(100vh - 150px), 920px);
  border-bottom: 1px solid var(--hairline);
}

.hero-left { position: relative; overflow: hidden; background: #060504; }
.particle-wrap { position: absolute; inset: 0; }
#particles { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }

.particle-wrap.no-webgl {
  background:
    radial-gradient(120% 90% at 78% 62%, rgba(255,244,230,.9) 0%, rgba(238,90,28,.55) 26%, rgba(120,45,12,.35) 48%, rgba(6,5,4,0) 72%),
    radial-gradient(rgba(238,90,28,.5) 1px, transparent 1.6px);
  background-size: auto, 11px 11px;
  background-color: #060504;
}

.hero-vol {
  position: absolute; top: clamp(20px, 3vw, 40px); left: clamp(20px, 3vw, 40px);
  color: #f4efe9; font-size: clamp(20px, 2vw, 28px); line-height: 1.35;
  font-weight: 300; letter-spacing: .02em;
  text-shadow: 0 2px 18px rgba(0,0,0,.5);
}

.hero-title-block {
  position: absolute; left: 0; bottom: 0;
  width: min(72%, 560px);
  background: var(--board);
  padding: clamp(20px, 2.6vw, 36px) clamp(24px, 3vw, 44px) clamp(24px, 3vw, 40px) clamp(20px, 3vw, 40px);
}
.hero-title-block .eyebrow { margin-bottom: 14px; }
.hero-title-block h1 {
  font-family: var(--serif);
  font-size: clamp(34px, 4.2vw, 62px);
  font-weight: 600;
  line-height: 1.18;
  letter-spacing: .01em;
}

.hero-right {
  display: flex; flex-direction: column;
  padding: clamp(28px, 4vw, 64px) var(--pad) clamp(24px, 3vw, 44px) clamp(24px, 3.4vw, 56px);
}
.hero-statement {
  font-family: var(--serif);
  font-size: clamp(36px, 3.9vw, 66px);
  font-weight: 500;
  line-height: 1.16;
  letter-spacing: .01em;
}
.explore {
  margin-top: clamp(24px, 3vh, 40px);
  align-self: flex-start;
  color: var(--ink); text-decoration: none;
  font-size: 15px; font-weight: 500; letter-spacing: .06em;
  border-bottom: 1px solid var(--ink);
  padding-bottom: 5px;
  transition: color .25s ease, border-color .25s ease;
}
.explore:hover { color: var(--orange); border-color: var(--orange); }
.hero-foot {
  margin-top: auto;
  display: flex; align-items: flex-end; justify-content: space-between; gap: 20px;
}

/* ---------- ticker ---------- */
.ticker {
  background: var(--orange); color: #1c0d04;
  overflow: hidden; white-space: nowrap;
  border-bottom: 1px solid var(--hairline);
}
.ticker-track { display: inline-flex; animation: ticker 36s linear infinite; }
.ticker:hover .ticker-track { animation-play-state: paused; }
.ticker-track span {
  display: inline-block;
  padding: 11px 0;
  font-size: 13px; font-weight: 600; letter-spacing: .2em;
}
@keyframes ticker { to { transform: translateX(-50%); } }

/* ---------- sections ---------- */
.section { padding: clamp(64px, 9vw, 120px) var(--pad); scroll-margin-top: 80px; }

.section-head {
  display: grid; grid-template-columns: 1.2fr 1fr;
  gap: clamp(24px, 4vw, 64px); align-items: end;
  margin-bottom: clamp(40px, 6vw, 72px);
}
.section-head .eyebrow { color: var(--orange); margin-bottom: 16px; }
.section-head h2 {
  font-family: var(--serif);
  font-size: clamp(30px, 3.4vw, 50px);
  font-weight: 600; line-height: 1.25;
}
.section-intro { color: var(--muted); font-size: 15px; max-width: 46ch; justify-self: end; }

/* services */
.service-grid {
  display: grid; grid-template-columns: repeat(3, 1fr);
  gap: 0 clamp(28px, 3.4vw, 56px);
  border-top: 1px solid var(--hairline);
}
.service {
  padding: clamp(24px, 2.6vw, 36px) 0 clamp(28px, 3vw, 40px);
  border-bottom: 1px solid var(--hairline);
}
.service .num {
  font-family: var(--serif); font-style: italic;
  color: var(--orange); font-size: 15px; letter-spacing: .1em;
  margin-bottom: 14px;
}
.service h3 {
  font-family: var(--serif); font-size: 23px; font-weight: 600;
  margin-bottom: 10px; transition: color .25s ease;
}
.service:hover h3 { color: var(--orange); }
.service p:not(.num):not(.tags) { color: var(--muted); font-size: 15px; }
.service .tags { margin-top: 14px; font-size: 12px; letter-spacing: .08em; color: var(--faint); }

/* about (dark band) */
.about { background: var(--dark-band); color: #f2ede7; }
.about .section-head { grid-template-columns: 1fr; margin-bottom: clamp(32px, 4vw, 52px); }
.about .section-head h2 { color: #f6f1ea; }
.about-intro { max-width: 72ch; color: var(--dark-muted); font-size: 16px; }

.stats {
  display: grid; grid-template-columns: repeat(4, 1fr);
  gap: clamp(20px, 3vw, 48px);
  margin: clamp(40px, 5vw, 64px) 0;
  padding: clamp(24px, 3vw, 40px) 0;
  border-top: 1px solid var(--dark-hairline);
  border-bottom: 1px solid var(--dark-hairline);
}
.stat-num {
  font-family: var(--serif);
  font-size: clamp(40px, 4.6vw, 64px);
  font-weight: 500; line-height: 1.1; color: #f6f1ea;
}
.stat-num .plus { color: var(--orange); }
.stat .caps { color: #8d867e; margin-top: 6px; }

.scope {
  border: 1px solid var(--dark-hairline);
  padding: clamp(20px, 2.6vw, 32px);
  margin-bottom: clamp(32px, 4vw, 48px);
}
.scope-label { color: var(--orange); margin-bottom: 12px; }
.scope p:not(.scope-label) { color: var(--dark-muted); font-size: 14px; line-height: 2; }

.facts { display: grid; grid-template-columns: 1fr 1fr; gap: 0 clamp(28px, 4vw, 64px); }
.facts > div {
  display: flex; justify-content: space-between; align-items: baseline; gap: 20px;
  padding: 13px 0; border-bottom: 1px solid var(--dark-hairline);
}
.facts dt { font-size: 12px; letter-spacing: .14em; color: #8d867e; flex: none; }
.facts dd { font-size: 14px; color: #e8e2da; text-align: right; }

/* process */
.steps { display: grid; grid-template-columns: repeat(4, 1fr); gap: clamp(24px, 3vw, 48px); }
.step { border-top: 1px solid var(--hairline); padding-top: 22px; position: relative; }
.step::before {
  content: ""; position: absolute; top: -4px; left: 0;
  width: 7px; height: 7px; border-radius: 50%; background: var(--orange);
}
.step-num {
  font-family: var(--serif); font-style: italic;
  font-size: 15px; color: var(--orange); letter-spacing: .1em; margin-bottom: 12px;
}
.step h3 { font-family: var(--serif); font-size: 21px; font-weight: 600; margin-bottom: 8px; }
.step p:not(.step-num) { color: var(--muted); font-size: 15px; }

/* contact */
.contact { border-top: 1px solid var(--hairline); }
.contact-grid { display: grid; grid-template-columns: 1.1fr 1fr; gap: clamp(32px, 5vw, 88px); }
.contact .eyebrow { color: var(--orange); margin-bottom: 16px; }
.contact-title {
  font-family: var(--serif);
  font-size: clamp(36px, 4.6vw, 72px);
  font-weight: 600; line-height: 1.2;
  margin-bottom: clamp(28px, 4vw, 44px);
}
.btn-pill {
  display: inline-flex; align-items: center; gap: 10px;
  background: var(--orange); color: #fff; text-decoration: none;
  padding: 15px 34px; border-radius: 999px;
  font-size: 15px; font-weight: 600; letter-spacing: .1em;
  transition: background .25s ease, transform .25s ease;
}
.btn-pill:hover { background: var(--orange-deep); transform: translateY(-2px); }

.contact-list { display: flex; flex-direction: column; }
.contact-row { padding: 22px 0; border-bottom: 1px solid var(--hairline); }
.contact-row:first-child { border-top: 1px solid var(--hairline); }
.contact-row .caps { margin-bottom: 8px; }
.contact-value {
  font-family: var(--serif); font-size: clamp(22px, 2.2vw, 30px); font-weight: 500;
  color: var(--ink); text-decoration: none;
  background-image: linear-gradient(var(--orange), var(--orange));
  background-size: 0% 1px; background-repeat: no-repeat; background-position: 0 100%;
  transition: background-size .35s ease, color .25s ease;
}
.contact-value:hover { color: var(--orange); background-size: 100% 1px; }
.contact-addr { font-size: 15px; color: var(--ink); }
.contact-addr-sub { margin-top: 8px; font-size: 13px; color: var(--faint); }

/* footer */
.footer {
  background: var(--dark-band); color: #cfc8c0;
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px; flex-wrap: wrap;
  padding: clamp(28px, 3.4vw, 44px) var(--pad);
}
.footer-brand { display: flex; align-items: center; gap: 16px; }
.footer-brand .flower { width: 34px; height: 34px; }
.footer-name { font-family: var(--serif); font-size: 17px; font-weight: 600; color: #f2ede7; }
.footer .caps { color: #7d766e; }
.footer-meta { text-align: right; font-size: 13px; color: #8d867e; }
.footer-meta a { color: #b6afa7; text-decoration: none; }
.footer-meta a:hover { color: var(--orange); }

/* ---------- reveal ---------- */
.js .reveal { opacity: 0; transform: translateY(26px); transition: opacity .8s ease, transform .8s cubic-bezier(.2,.6,.2,1); }
.js .reveal.in { opacity: 1; transform: none; }
.service-grid .reveal:nth-child(2), .steps .reveal:nth-child(2) { transition-delay: .1s; }
.service-grid .reveal:nth-child(3), .steps .reveal:nth-child(3) { transition-delay: .2s; }
.service-grid .reveal:nth-child(4), .steps .reveal:nth-child(4) { transition-delay: .12s; }
.service-grid .reveal:nth-child(5) { transition-delay: .22s; }
.service-grid .reveal:nth-child(6) { transition-delay: .32s; }

.js .reveal-hero { opacity: 0; transform: translateY(22px); animation: heroIn 1s cubic-bezier(.2,.6,.2,1) forwards; animation-delay: var(--d, 0s); }
@keyframes heroIn { to { opacity: 1; transform: none; } }

/* ---------- responsive ---------- */
@media (max-width: 1080px) {
  .service-grid { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: repeat(2, 1fr); }
  .hero { grid-template-columns: 1.1fr 1fr; }
}

@media (max-width: 900px) {
  .margin-deco { display: none; }
  .nav-links {
    position: absolute; top: 100%; left: 0; right: 0;
    flex-direction: column; align-items: stretch; gap: 0;
    background: var(--board); border-bottom: 1px solid var(--hairline);
    max-height: 0; overflow: hidden; transition: max-height .4s ease;
  }
  .nav-links.open { max-height: 340px; }
  .nav-links a { padding: 16px var(--pad); border-top: 1px solid var(--hairline); letter-spacing: .1em; }
  .nav-cta { margin: 14px var(--pad) 18px; text-align: center; border-top: 0 !important; }
  .nav-toggle { display: flex; }

  .hero { grid-template-columns: 1fr; height: auto; }
  .hero-left { height: 62vh; min-height: 420px; }
  .hero-title-block { width: min(86%, 520px); }
  .hero-right { padding: 32px var(--pad) 36px; }
  .hero-foot { margin-top: 40px; }

  .section-head { grid-template-columns: 1fr; align-items: start; }
  .section-intro { justify-self: start; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .facts { grid-template-columns: 1fr; }
  .contact-grid { grid-template-columns: 1fr; }
  .footer { flex-direction: column; align-items: flex-start; }
  .footer-meta { text-align: left; }
}

@media (max-width: 620px) {
  .service-grid { grid-template-columns: 1fr; }
  .steps { grid-template-columns: 1fr; }
  .brand-en { display: none; }
  .hero-vol { font-size: 18px; }
}

/* ---------- reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .spin, .ticker-track { animation: none; }
  .js .reveal, .js .reveal-hero { opacity: 1; transform: none; transition: none; animation: none; }
}