:root {
  --bg: #fcfcfb;
  --fg: #1b1b19;
  --muted: #6e6e68;
  --line: #e7e6e1;
  --card: #ffffff;
  --accent: #0f5c4d;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.75 -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }

.wrap {
  max-width: 880px;
  margin: 0 auto;
  padding: 0 24px;
}

/* header */
header.site { border-bottom: 1px solid var(--line); }
header.site .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}
.brand { font-weight: 600; font-size: 15px; letter-spacing: .02em; }
.brand .dot { color: var(--accent); }
nav { display: flex; align-items: center; gap: 22px; }
nav a { font-size: 14px; color: var(--muted); transition: color .15s; }
nav a:hover { color: var(--fg); }
nav a.lang {
  color: var(--accent);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 1px 10px;
  font-size: 12px;
}

/* hero */
.hero { padding: 84px 0 64px; border-bottom: 1px solid var(--line); }
.hero h1 {
  margin: 0 0 18px;
  font-size: 40px;
  line-height: 1.28;
  letter-spacing: -.015em;
  font-weight: 600;
  max-width: 720px;
}
.hero .intro {
  margin: 0;
  max-width: 620px;
  color: var(--muted);
  font-size: 17px;
  line-height: 1.8;
}

/* sections */
section { padding: 60px 0; border-bottom: 1px solid var(--line); }
section:last-of-type { border-bottom: none; }
h2 {
  font-size: 12px;
  letter-spacing: .16em;
  text-transform: uppercase;
  color: var(--muted);
  font-weight: 600;
  margin: 0 0 26px;
}

/* cards */
.grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
}
.card {
  display: block;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 22px 24px;
  transition: border-color .15s, transform .15s, box-shadow .15s;
}
.card:hover {
  border-color: #cfcec7;
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0,0,0,.05);
}
.card h3 {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 9px;
  flex-wrap: wrap;
}
.card p { margin: 0; color: var(--muted); font-size: 14px; line-height: 1.65; }
.badge {
  font-size: 11px;
  font-weight: 500;
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 1px 8px;
  letter-spacing: .02em;
}

/* updates */
.updates { list-style: none; margin: 0; padding: 0; }
.updates li {
  display: flex;
  align-items: baseline;
  gap: 18px;
  padding: 13px 0;
  border-top: 1px solid var(--line);
}
.updates li:first-child { border-top: none; }
.updates time {
  flex: 0 0 88px;
  color: var(--muted);
  font-size: 13px;
  font-variant-numeric: tabular-nums;
}
.updates .src {
  flex: 0 0 104px;
  font-size: 12px;
  color: var(--accent);
  letter-spacing: .02em;
}
.updates a { font-size: 15px; border-bottom: 1px solid transparent; }
.updates a:hover { border-bottom-color: currentColor; }

/* prose / pages */
.page { padding: 72px 0; }
.page h1 { margin: 0 0 28px; font-size: 32px; line-height: 1.3; font-weight: 600; }
.prose { max-width: 680px; }
.prose p { margin: 0 0 18px; color: #33332f; }
.prose h2 {
  font-size: 18px;
  letter-spacing: 0;
  text-transform: none;
  color: var(--fg);
  margin: 34px 0 12px;
}
.prose ul { padding-left: 22px; }
.prose li { margin: 6px 0; }
.prose a { color: var(--accent); border-bottom: 1px solid rgba(15,92,77,.3); }
.prose a:hover { border-bottom-color: var(--accent); }
.prose code {
  background: #f0efe9;
  padding: 1px 5px;
  border-radius: 4px;
  font-size: 13px;
}
.back { margin-top: 44px; font-size: 14px; color: var(--muted); }
.back a:hover { color: var(--fg); }

/* footer */
footer.site {
  padding: 34px 0 60px;
  color: var(--muted);
  font-size: 13px;
}
footer.site .wrap {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

/* mobile */
@media (max-width: 640px) {
  .hero { padding: 56px 0 44px; }
  .hero h1 { font-size: 30px; }
  .hero .intro { font-size: 16px; }
  section { padding: 44px 0; }
  .grid { grid-template-columns: 1fr; }
  nav { gap: 14px; }
  nav a { font-size: 13px; }
  .updates li { flex-wrap: wrap; gap: 2px 12px; }
  .updates time { flex-basis: auto; }
  .updates .src { flex-basis: auto; }
}