:root {
  --brand: #1f8a4c;
  --brand-dark: #156e3c;
  --ink: #1a2430;
  --muted: #5b6b7b;
  --line: #e4e9ee;
  --bg: #ffffff;
  --bg-soft: #f6f9f7;
  --max: 1080px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
}
a { color: var(--brand-dark); text-decoration: none; }
a:hover { text-decoration: underline; }

/* Header */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: rgba(255,255,255,.92);
  backdrop-filter: saturate(160%) blur(8px);
  border-bottom: 1px solid var(--line);
}
.nav {
  max-width: var(--max); margin: 0 auto; padding: 14px 20px;
  display: flex; align-items: center; gap: 18px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 18px; color: var(--ink); }
.brand .logo {
  width: 30px; height: 30px; border-radius: 8px;
  background: linear-gradient(135deg, var(--brand), #38b06c);
  display: inline-flex; align-items: center; justify-content: center;
  color: #fff; font-weight: 800; font-size: 16px;
}
.nav-links { display: flex; gap: 18px; margin-left: auto; flex-wrap: wrap; }
.nav-links a { color: var(--muted); font-size: 15px; }
.nav-links a:hover { color: var(--brand-dark); text-decoration: none; }
.lang-btn {
  border: 1px solid var(--line); background: #fff; color: var(--ink);
  border-radius: 999px; padding: 6px 14px; font-size: 14px; cursor: pointer;
}
.lang-btn:hover { border-color: var(--brand); color: var(--brand-dark); }

/* Layout */
.container { max-width: var(--max); margin: 0 auto; padding: 0 20px; }
.section { padding: 56px 0; }
.section.soft { background: var(--bg-soft); }

/* Hero */
.hero { padding: 72px 0 56px; }
.hero h1 { font-size: 40px; line-height: 1.25; margin: 0 0 16px; letter-spacing: -.5px; }
.hero p.lead { font-size: 19px; color: var(--muted); max-width: 720px; margin: 0 0 28px; }
.btn {
  display: inline-block; background: var(--brand); color: #fff;
  padding: 12px 24px; border-radius: 10px; font-weight: 600; font-size: 16px;
}
.btn:hover { background: var(--brand-dark); text-decoration: none; }
.btn.ghost { background: #fff; color: var(--brand-dark); border: 1px solid var(--brand); margin-left: 10px; }

/* Cards */
.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card { background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 24px; }
.card h3 { margin: 0 0 8px; font-size: 18px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }
.card .ic { font-size: 26px; margin-bottom: 10px; }

h2.section-title { font-size: 28px; margin: 0 0 8px; letter-spacing: -.3px; }
.section-sub { color: var(--muted); margin: 0 0 32px; font-size: 16px; }

/* Legal / doc pages */
.doc { max-width: 820px; margin: 0 auto; padding: 48px 20px 64px; }
.doc h1 { font-size: 32px; margin: 0 0 6px; }
.doc .updated { color: var(--muted); font-size: 14px; margin: 0 0 32px; }
.doc h2 { font-size: 21px; margin: 34px 0 10px; }
.doc h3 { font-size: 17px; margin: 22px 0 8px; }
.doc p, .doc li { color: #2b3744; }
.doc ul { padding-left: 22px; }
.doc li { margin: 6px 0; }
.doc table { width: 100%; border-collapse: collapse; margin: 16px 0; font-size: 15px; }
.doc th, .doc td { border: 1px solid var(--line); padding: 10px 12px; text-align: left; vertical-align: top; }
.doc th { background: var(--bg-soft); }
.callout {
  background: var(--bg-soft); border: 1px solid var(--line);
  border-left: 4px solid var(--brand); border-radius: 8px; padding: 14px 18px; margin: 18px 0;
}

/* Info table for contact/about */
.info-list { list-style: none; padding: 0; margin: 0; }
.info-list li { padding: 10px 0; border-bottom: 1px solid var(--line); }
.info-list b { display: inline-block; min-width: 140px; color: var(--muted); font-weight: 600; }

/* Footer */
.site-footer { background: #11201a; color: #c7d4cc; margin-top: 40px; }
.footer-inner { max-width: var(--max); margin: 0 auto; padding: 40px 20px 28px; }
.footer-cols { display: flex; flex-wrap: wrap; gap: 40px; justify-content: space-between; }
.footer-cols h4 { color: #fff; font-size: 15px; margin: 0 0 12px; }
.footer-cols a { display: block; color: #9fb3a8; font-size: 14px; margin: 6px 0; }
.footer-cols a:hover { color: #fff; text-decoration: none; }
.footer-bottom { border-top: 1px solid #24382f; margin-top: 28px; padding-top: 18px; font-size: 13px; color: #8aa093; }
.footer-bottom a { color: #8aa093; }

/* Language toggle visibility */
[data-lang] .en, [data-lang] .zh { display: none; }
[data-lang="en"] .en { display: revert; }
[data-lang="zh"] .zh { display: revert; }

@media (max-width: 760px) {
  .grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 30px; }
  .nav { gap: 10px; }
  .nav-links { gap: 12px; }
  .btn.ghost { margin-left: 0; margin-top: 10px; }
}