:root {
  --bg: #f6f7f9;
  --card: #ffffff;
  --text: #1f2937;
  --muted: #5b6470;
  --brand: #0f766e;
  --brand-dark: #115e59;
  --accent: #3157a4;
  --border: #d9dee8;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "IBM Plex Sans", "Noto Sans SC", "PingFang SC", sans-serif;
  color: var(--text);
  background: linear-gradient(180deg, #eef6f3 0%, var(--bg) 34%, #ffffff 100%);
}

.container {
  width: min(1040px, 92vw);
  margin: 0 auto;
}

.hero {
  padding: 40px 0 28px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.4px;
}

.version {
  display: inline-block;
  margin: 22px 0 0;
  padding: 4px 8px;
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--accent);
  background: #fff;
  font-weight: 700;
}

.lang-switch {
  display: inline-flex;
  gap: 8px;
}

.lang-btn {
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
  padding: 6px 10px;
  border-radius: 999px;
  cursor: pointer;
}

.lang-btn.active {
  background: var(--brand);
  color: #fff;
  border-color: var(--brand);
}

h1 {
  font-size: clamp(28px, 4vw, 44px);
  line-height: 1.1;
  margin: 18px 0 12px;
}

.subtitle {
  color: var(--muted);
  margin: 0 0 18px;
  font-size: 18px;
}

.cta-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 10px 14px;
  border-radius: 10px;
  text-decoration: none;
  background: var(--brand);
  color: white;
  font-weight: 600;
}

.btn.ghost {
  background: transparent;
  border: 1px solid var(--brand);
  color: var(--brand-dark);
}

main {
  padding-bottom: 24px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 18px;
  margin: 14px 0;
}

.card h2 {
  margin: 0 0 10px;
  font-size: 24px;
}

.card ul {
  margin: 0;
  padding-left: 20px;
  line-height: 1.7;
}

.module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}

.module {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px;
  background: #fbfcfe;
}

.module h3 {
  margin: 0 0 8px;
}

.module p {
  margin: 0;
  color: var(--muted);
}

pre {
  margin: 0;
  background: #101726;
  color: #c9f3e7;
  border-radius: 10px;
  padding: 14px;
  overflow: auto;
}

.table-wrap {
  overflow: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
}

th,
td {
  border-bottom: 1px solid var(--border);
  text-align: left;
  padding: 10px 8px;
  white-space: nowrap;
}

th {
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.4px;
  color: var(--muted);
}

.note {
  color: var(--muted);
  margin: 10px 0 0;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 12px;
}

.link-card {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px;
  text-decoration: none;
  color: inherit;
  background: #fbfcfe;
}

.link-card h3 {
  margin: 0 0 6px;
}

.link-card p {
  margin: 0;
  color: var(--muted);
}

.footer {
  border-top: 1px solid var(--border);
  padding: 18px 0 24px;
  color: var(--muted);
}

.lang {
  display: none;
}

html[lang="zh-CN"] .lang-zh,
html[lang="en"] .lang-en {
  display: inline;
}

html[lang="zh-CN"] li.lang-zh,
html[lang="en"] li.lang-en,
html[lang="zh-CN"] p.lang-zh,
html[lang="en"] p.lang-en {
  display: block;
}

@media (max-width: 640px) {
  .hero {
    padding-top: 22px;
  }

  .card {
    padding: 14px;
  }
}