:root {
  --bg: #f7f8fa;
  --surface: #ffffff;
  --ink: #0a2540;
  --ink-soft: #4b5b6f;
  --accent: #0070f3;
  --accent-soft: #e6f0ff;
  --border: #e2e8f0;
  --code-bg: #f1f5f9;
  --radius: 14px;
  --maxw: 760px;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--ink);
  color: #fff;
  padding: 8px 12px;
  z-index: 999;
}
.skip-link:focus { left: 8px; top: 8px; }

/* Header */
.site-header {
  background: var(--ink);
  color: #fff;
  position: sticky;
  top: 0;
  z-index: 10;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-top: 14px;
  padding-bottom: 14px;
  min-height: 56px;
}
.brand {
  color: #fff;
  display: flex;
  flex-direction: column;
  gap: 2px;
  line-height: 1.1;
}
.brand:hover { text-decoration: none; }
.brand-mark {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.brand-accent { color: #4ea4ff; }
.brand-sub {
  font-size: 12px;
  font-weight: 500;
  color: #bcd3f1;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.lang-switcher {
  display: flex;
  gap: 4px;
  background: rgba(255,255,255,0.08);
  border-radius: 999px;
  padding: 4px;
  flex-wrap: wrap;
}
.lang-switcher a {
  color: #cfdbeb;
  text-decoration: none;
  font-size: 13px;
  font-weight: 600;
  padding: 6px 10px;
  border-radius: 999px;
  line-height: 1;
}
.lang-switcher a:hover { color: #fff; background: rgba(255,255,255,0.08); }
.lang-switcher a.is-current {
  background: #fff;
  color: var(--ink);
}

/* Doc */
main {
  padding-top: 28px;
  padding-bottom: 48px;
}
.doc {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 24px;
  box-shadow: 0 1px 2px rgba(15,30,52,0.04);
}
.doc-meta {
  margin: 0 0 12px 0;
  color: var(--ink-soft);
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.doc h1 {
  margin: 0 0 12px 0;
  font-size: 30px;
  letter-spacing: -0.02em;
  line-height: 1.15;
}
.doc h2 {
  margin: 32px 0 12px 0;
  font-size: 22px;
  letter-spacing: -0.01em;
  border-top: 1px solid var(--border);
  padding-top: 24px;
}
.doc h2:first-of-type { border-top: none; padding-top: 0; }
.doc h3 {
  margin: 24px 0 8px 0;
  font-size: 18px;
}
.doc p, .doc li { color: var(--ink); }
.doc blockquote {
  margin: 16px 0;
  padding: 12px 16px;
  background: var(--accent-soft);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  color: var(--ink);
}
.doc blockquote p { margin: 0; }
.doc ul, .doc ol { padding-left: 22px; }
.doc li { margin: 4px 0; }
.doc code {
  background: var(--code-bg);
  padding: 1px 6px;
  border-radius: 4px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92em;
  word-break: break-word;
}
.doc hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 28px 0;
}
.doc strong { font-weight: 700; }
.doc a { word-break: break-word; }

.back-link {
  margin-top: 24px;
  font-size: 14px;
}

/* Index hero */
.hero {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 36px 24px;
  margin-bottom: 24px;
  text-align: center;
}
.hero h1 {
  margin: 0 0 8px 0;
  font-size: 32px;
  letter-spacing: -0.02em;
}
.hero .lead {
  margin: 0;
  color: var(--ink-soft);
  font-size: 17px;
}

.docs-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}
@media (max-width: 600px) {
  .docs-grid { grid-template-columns: 1fr; }
}
.doc-card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px 22px;
  color: var(--ink);
  transition: transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease;
}
.doc-card:hover {
  text-decoration: none;
  border-color: var(--accent);
  transform: translateY(-1px);
  box-shadow: 0 6px 18px rgba(15,30,52,0.08);
}
.doc-card h2 {
  margin: 0 0 6px 0;
  font-size: 20px;
  letter-spacing: -0.01em;
}
.doc-card p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 14px;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 22px 0;
  background: var(--surface);
  margin-top: 32px;
}
.site-footer p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 13px;
  text-align: center;
}

/* Print */
@media print {
  .site-header, .site-footer, .back-link, .lang-switcher, .skip-link { display: none; }
  body { background: #fff; font-size: 12pt; }
  .container { max-width: none; padding: 0; }
  .doc {
    border: none;
    box-shadow: none;
    padding: 0;
  }
  a { color: inherit; text-decoration: underline; }
}