:root {
  --bg: #fafafa;
  --surface: #ffffff;
  --panel: #f4f4f5;
  --border: #e8e8e8;
  --border-strong: #cfcfcf;
  --text: #171717;
  --text-2: #444444;
  --muted: #6b6b6b;
  --ink: #111111;
  --radius: 12px;
  --max: 1280px;
  --font: "Geist", "Inter", "Noto Sans SC", system-ui, -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --mono: "Geist Mono", ui-monospace, SFMono-Regular, Menlo, monospace;
  color-scheme: light;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 80px; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
::selection { background: #171717; color: #fff; }
a { color: inherit; text-decoration: none; }
img, svg { max-width: 100%; }
h1, h2, h3 { line-height: 1.1; margin: 0; letter-spacing: -0.035em; font-weight: 500; text-wrap: balance; }
p { margin: 0; }
p, li, dd, summary, .stat span { text-wrap: pretty; }
ul, ol { margin: 0; padding: 0; list-style: none; }

.wrap { width: 100%; max-width: var(--max); margin: 0 auto; padding: 0 20px; }
@media (min-width: 720px) { .wrap { padding: 0 32px; } }

.grad-text { color: inherit; white-space: nowrap; }
.eyebrow {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 14px;
}
.skip {
  position: absolute; left: -999px; top: 8px;
  background: var(--ink); color: #fff; padding: 8px 14px; border-radius: 999px; z-index: 100;
}
.skip:focus { left: 8px; }

/* ---------- nav ---------- */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 50;
  transition: background 0.25s, border-color 0.25s;
  border-bottom: 1px solid transparent;
}
.nav.scrolled {
  background: rgba(250, 250, 250, 0.82);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-color: var(--border);
}
.nav-inner { display: flex; align-items: center; height: 60px; gap: 32px; }
.brand { display: flex; align-items: center; gap: 9px; font-weight: 600; font-size: 17px; letter-spacing: -0.03em; }
.brand img { width: 26px; height: 26px; border-radius: 6px; }
.nav-links { display: flex; align-items: center; gap: 24px; font-size: 14px; color: var(--muted); margin-right: auto; }
.nav-links a:hover { color: var(--text); }
.nav-actions { display: flex; align-items: center; gap: 8px; }
.lang {
  font-size: 14px; font-weight: 500; color: var(--text); background: var(--surface);
  border: 1px solid var(--border); border-radius: 999px; padding: 6px 14px;
}
.lang:hover { border-color: var(--border-strong); }
.menu-btn {
  display: none; background: var(--surface); border: 1px solid var(--border); border-radius: 999px;
  color: var(--text); width: 36px; height: 36px; cursor: pointer;
}
@media (max-width: 860px) {
  .nav-inner { gap: 12px; justify-content: space-between; }
  .menu-btn { display: inline-flex; align-items: center; justify-content: center; }
  .nav-links {
    position: absolute; top: 60px; left: 0; right: 0; flex-direction: column; align-items: flex-start;
    gap: 0; background: var(--bg); border-bottom: 1px solid var(--border);
    padding: 8px 20px 16px; display: none; margin: 0;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 12px 0; width: 100%; font-size: 16px; color: var(--text); }
  .nav-cta { display: none; }
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px; font: inherit; font-weight: 500; font-size: 14px;
  padding: 10px 18px; border-radius: 999px; border: 1px solid var(--border);
  cursor: pointer; transition: background 0.2s, border-color 0.2s, transform 0.15s;
}
.btn-primary { background: var(--ink); border-color: var(--ink); color: #fff; }
.btn-primary:hover { background: #333; border-color: #333; }
.btn-ghost { background: var(--surface); color: var(--text); }
.btn-ghost:hover { border-color: var(--border-strong); }
.btn-sm { padding: 7px 14px; }

/* ---------- hero ---------- */
.hero { position: relative; padding: 170px 0 110px; overflow: hidden; isolation: isolate; text-align: center; }
#net { position: absolute; inset: 0; width: 100%; height: 100%; z-index: -1; opacity: 0.55; }
.hero .eyebrow { margin-bottom: 22px; }
.hero h1 { font-size: clamp(40px, 6.6vw, 80px); max-width: 15ch; margin: 0 auto; letter-spacing: -0.05em; }
:lang(zh) .hero h1 { font-size: clamp(24px, 6.6vw, 80px); max-width: none; letter-spacing: -0.02em; }
/* CJK headings: break only at spaces / phrase boundaries, never between two characters of a word, so no browser can strand a lone last character */
:lang(zh) h1, :lang(zh) h2, :lang(zh) h3 { word-break: keep-all; overflow-wrap: break-word; }
.hero .lead { margin: 26px auto 0; max-width: 60ch; font-size: clamp(16px, 1.8vw, 19px); color: var(--muted); }
.hero-cta { margin-top: 32px; display: flex; flex-wrap: wrap; gap: 10px; justify-content: center; }
.hero-exp { margin-top: 36px; font-size: 13px; color: var(--muted); font-family: var(--mono); }
.hero-exp b { color: var(--text); font-weight: 500; }

/* wordmark row (domains + team) */
.domains, .logos { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 14px 40px; }
.domains { margin-top: 110px; text-align: left; }
.chip, .logos span {
  font-size: clamp(18px, 2.3vw, 27px); font-weight: 600; letter-spacing: -0.04em; color: var(--ink);
}
.logos { margin: 0 0 56px; }
@media (max-width: 720px) { .domains, .logos { justify-content: flex-start; } }

/* ---------- sections ---------- */
section { padding: 112px 0; position: relative; }
.sec-head { max-width: 780px; margin-bottom: 56px; }
.sec-head h2 { font-size: clamp(30px, 4.2vw, 52px); letter-spacing: -0.045em; }
.sec-head p { margin-top: 16px; color: var(--muted); font-size: 17px; max-width: 54ch; }

.grid { display: grid; gap: 16px; }
.g-services { grid-template-columns: repeat(auto-fit, minmax(min(100%, 300px), 1fr)); }
.g-cases { grid-template-columns: repeat(auto-fit, minmax(min(100%, 380px), 1fr)); }

.card {
  --mx: 50%; --my: 0%;
  position: relative; padding: 24px; border-radius: var(--radius); border: 1px solid var(--border);
  background: var(--surface); overflow: hidden; transition: border-color 0.2s;
}
.card::before {
  content: ""; position: absolute; inset: 0; pointer-events: none; opacity: 0; transition: opacity 0.3s;
  background: radial-gradient(320px circle at var(--mx) var(--my), rgba(0, 0, 0, 0.035), transparent 60%);
}
.card:hover { border-color: var(--border-strong); }
.card:hover::before { opacity: 1; }
.card h3 { font-size: 19px; margin: 0 0 8px; font-weight: 600; letter-spacing: -0.025em; }
.card p { color: var(--muted); font-size: 15px; }
.card ul { margin-top: 18px; display: grid; gap: 7px; }
.card li { position: relative; padding-left: 16px; color: var(--text-2); font-size: 14.5px; }
.card li::before { content: ""; position: absolute; left: 0; top: 0.8em; width: 7px; height: 1px; background: #9a9a9a; }

/* pale illustration panel on top of service cards */
.icon {
  margin: -24px -24px 22px; height: 150px; display: grid; place-items: center; color: var(--ink);
  background-color: var(--panel); border-bottom: 1px solid var(--border);
  background-image: radial-gradient(#d4d4d8 1px, transparent 1px); background-size: 14px 14px;
}
.icon svg { width: 66px; height: 66px; padding: 18px; stroke-width: 1.3; border-radius: 16px; border: 1px solid var(--border); background: var(--surface); }
.card.featured { border-color: #bdbdbd; }
.tag {
  display: inline-block; font-family: var(--mono); font-size: 10.5px; letter-spacing: 0.06em; text-transform: uppercase;
  padding: 2px 8px; border-radius: 999px; background: var(--ink); color: #fff; margin-left: 6px; vertical-align: middle; font-weight: 500;
}

/* ---------- approach ---------- */
.approach { display: grid; gap: 64px; grid-template-columns: 1.15fr 0.85fr; align-items: center; }
@media (max-width: 900px) { .approach { grid-template-columns: 1fr; gap: 40px; } }
.steps { counter-reset: s; display: grid; gap: 0; }
.steps li { counter-increment: s; position: relative; padding: 22px 0 22px 52px; border-top: 1px solid var(--border); }
.steps li:last-child { border-bottom: 1px solid var(--border); }
.steps li::before {
  content: counter(s, decimal-leading-zero); position: absolute; left: 0; top: 25px;
  font-family: var(--mono); font-size: 13px; color: var(--muted);
}
.steps h3 { font-size: 17px; font-weight: 600; letter-spacing: -0.02em; }
.steps p { color: var(--muted); font-size: 15px; margin-top: 4px; }
.triad { width: 100%; max-width: 440px; margin: 0 auto; display: block; }

/* ---------- principles / team ---------- */
.g-4 { grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 32px 28px; }
.principle { padding-top: 18px; border-top: 1px solid var(--ink); }
.principle h3 { font-size: 16.5px; font-weight: 600; margin-bottom: 8px; letter-spacing: -0.02em; }
.principle p { color: var(--muted); font-size: 15px; }

/* ---------- cases ---------- */
.case { padding: 28px; }
.case .meta { font-family: var(--mono); font-size: 11.5px; color: var(--muted); letter-spacing: 0.08em; text-transform: uppercase; }
.case h3 { margin: 10px 0 0; font-size: 22px; }
.case dl { margin: 22px 0 0; display: grid; gap: 14px; }
.case dt { font-family: var(--mono); font-size: 11px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); }
.case dd { margin: 3px 0 0; color: var(--text-2); font-size: 14.5px; }
.stack { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 20px; }
.stack span { font-family: var(--mono); font-size: 11.5px; padding: 3px 9px; border-radius: 999px; background: var(--panel); border: 1px solid var(--border); color: var(--text-2); }
.links { margin-top: 22px; display: flex; flex-wrap: wrap; gap: 18px; font-size: 14px; font-weight: 500; }
.links a { color: var(--ink); }
.links a:hover { text-decoration: underline; text-underline-offset: 3px; }

.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 1px; margin-top: 16px; border: 1px solid var(--border); border-radius: var(--radius); overflow: hidden; background: var(--border); }
.stat { background: var(--surface); padding: 28px 24px; }
.stat b { display: block; font-size: clamp(30px, 4vw, 44px); font-weight: 500; letter-spacing: -0.05em; line-height: 1.1; }
.stat span { color: var(--muted); font-size: 14px; display: block; margin-top: 6px; }

/* ---------- faq ---------- */
.faq { max-width: 820px; border-top: 1px solid var(--border); }
.faq details { border-bottom: 1px solid var(--border); }
.faq summary { cursor: pointer; padding: 20px 0; font-weight: 500; font-size: 17px; letter-spacing: -0.02em; list-style: none; display: flex; justify-content: space-between; gap: 16px; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-family: var(--mono); color: var(--muted); font-size: 20px; line-height: 1; }
.faq details[open] summary::after { content: "−"; }
.faq details p { padding: 0 0 22px; color: var(--muted); font-size: 15.5px; max-width: 70ch; }

/* ---------- cta / footer ---------- */
.cta-panel {
  position: relative; overflow: hidden; border-radius: 20px; padding: clamp(44px, 7vw, 88px) 24px; text-align: center;
  background: var(--ink); color: #fff;
  background-image: radial-gradient(rgba(255,255,255,.12) 1px, transparent 1px); background-size: 16px 16px;
}
.cta-panel h2 { font-size: clamp(30px, 4.6vw, 54px); max-width: 17ch; margin: 0 auto; letter-spacing: -0.045em; }
.cta-panel p { margin: 18px auto 30px; max-width: 54ch; color: #a8a8a8; }
.cta-panel .btn-primary { background: #fff; color: var(--ink); border-color: #fff; }
.cta-panel .btn-primary:hover { background: #e6e6e6; border-color: #e6e6e6; }
.footer { border-top: 1px solid var(--border); padding: 36px 0 56px; color: var(--muted); font-size: 14px; }
.footer-inner { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 20px; }
.footer a:hover { color: var(--text); }
.footer-links { display: flex; flex-wrap: wrap; gap: 22px; }

/* ---------- progressive reveal (only when JS adds .js) ---------- */
.js .reveal { opacity: 0; transform: translateY(16px); transition: opacity 0.6s ease, transform 0.6s ease; }
.js .reveal.in { opacity: 1; transform: none; }

:focus-visible { outline: 2px solid #0070f3; outline-offset: 3px; border-radius: 6px; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .js .reveal { opacity: 1; transform: none; transition: none; }
  .card, .btn { transition: none; }
}

.nb { white-space: nowrap; }