/* Design 9a shared chrome + article typography for the blog (dark-only, matches the landing). */
:root {
  --bg-canvas: #0d1117;
  --bg-inset: #010409;
  --bg-card: #161b22;
  --border-default: #30363d;
  --border-muted: #21262d;
  --fg-default: #e6edf3;
  --fg-secondary: #c9d1d9;
  --fg-muted: #8b949e;
  --fg-subtle: #6e7681;
  --accent-text: #58a6ff;
  --success-fg: #3fb950;
  --danger-fg: #f85149;
  --btn-primary-bg: #238636;
  --btn-primary-hover: #2ea043;
  --diff-add-bg: rgba(46, 160, 67, 0.15);
  --diff-del-bg: rgba(248, 81, 73, 0.12);
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  color-scheme: dark;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg-canvas);
  color: var(--fg-default);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans", Helvetica, Arial, sans-serif;
  font-size: 15px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent-text); text-decoration: none; }
a:hover { text-decoration: underline; }
.wrap { max-width: 1180px; margin: 0 auto; padding: 0 32px; }

.btn-primary {
  display: inline-block; padding: 10px 20px; border-radius: 6px;
  background: var(--btn-primary-bg); color: #ffffff; font-weight: 600;
  font-size: 15px; line-height: 1.4; border: 1px solid rgba(240, 246, 252, 0.1);
}
.btn-primary:hover { background: var(--btn-primary-hover); text-decoration: none; }

.site-header { background: var(--bg-inset); border-bottom: 1px solid var(--border-muted); }
.site-header .wrap { display: flex; align-items: center; gap: 24px; height: 58px; }
.wordmark { display: inline-flex; align-items: center; gap: 10px; color: var(--fg-default); font-size: 17px; font-weight: 700; }
.wordmark:hover { text-decoration: none; }
.logo-mark {
  width: 26px; height: 26px; display: inline-flex; align-items: center; justify-content: center;
  border-radius: 6px; background: var(--btn-primary-bg); color: #fff;
  font-family: var(--mono); font-size: 15px; font-weight: 700;
}
.site-nav { margin-left: auto; display: flex; align-items: center; gap: 22px; font-size: 14px; }
.site-nav a { color: var(--fg-secondary); }
.site-nav a:hover { color: var(--fg-default); text-decoration: none; }
.site-nav a.active { color: var(--fg-default); font-weight: 600; }
.site-nav .btn-primary { padding: 7px 14px; font-size: 14px; color: #fff; }

.site-footer {
  border-top: 1px solid var(--border-muted); background: var(--bg-inset);
  padding: 26px 0; text-align: center; font-size: 13px; color: var(--fg-subtle);
}
.site-footer a { color: var(--fg-muted); margin: 0 10px; }

/* ===== Blog index ===== */
.blog-head { padding: 64px 0 8px; }
.blog-head h1 { margin: 0 0 10px; font-size: 36px; font-weight: 800; letter-spacing: -0.02em; }
.blog-head p { margin: 0; color: var(--fg-muted); font-size: 16px; max-width: 40rem; }
.post-list { padding: 40px 0 88px; display: grid; gap: 18px; max-width: 760px; }
.post-card {
  display: block; border: 1px solid var(--border-default); border-radius: 10px;
  background: var(--bg-card); padding: 22px 24px; color: inherit;
}
.post-card:hover { background: #1c2129; text-decoration: none; }
.post-card .meta { margin: 0 0 6px; font-family: var(--mono); font-size: 12.5px; color: var(--fg-subtle); }
.post-card h2 { margin: 0 0 8px; font-size: 20px; color: var(--fg-default); letter-spacing: -0.01em; }
.post-card p.teaser { margin: 0; color: var(--fg-muted); font-size: 14px; }

/* ===== Article ===== */
.article { max-width: 720px; margin: 0 auto; padding: 56px 32px 40px; }
.article .meta { margin: 0 0 14px; font-family: var(--mono); font-size: 13px; color: var(--fg-subtle); }
.article h1 { margin: 0 0 18px; font-size: 34px; line-height: 1.2; font-weight: 800; letter-spacing: -0.02em; }
.article .lede { color: var(--fg-secondary); font-size: 17px; line-height: 1.6; margin: 0 0 8px; }
.article h2 { margin: 40px 0 12px; font-size: 23px; font-weight: 700; letter-spacing: -0.01em; }
.article h3 { margin: 28px 0 8px; font-size: 17px; }
.article p { margin: 0 0 16px; color: var(--fg-secondary); font-size: 15.5px; line-height: 1.65; }
.article ul, .article ol { margin: 0 0 16px; padding-left: 22px; color: var(--fg-secondary); font-size: 15.5px; line-height: 1.65; }
.article li { margin-bottom: 6px; }
.article code {
  font-family: var(--mono); font-size: 13.5px; background: var(--bg-card);
  border: 1px solid var(--border-muted); border-radius: 4px; padding: 1px 5px;
}
.article blockquote {
  margin: 0 0 16px; padding: 10px 16px; border-left: 3px solid var(--border-default);
  color: var(--fg-muted);
}
.article hr { border: none; border-top: 1px solid var(--border-muted); margin: 36px 0; }

/* Inline diff block (same language as the landing PR mock) */
.pr-card {
  border: 1px solid var(--border-default); border-radius: 10px; overflow: hidden;
  background: var(--bg-card); font-size: 12.5px; margin: 22px 0;
}
.pr-head {
  display: flex; align-items: center; gap: 9px; padding: 10px 14px;
  border-bottom: 1px solid var(--border-muted); background: var(--bg-card);
}
.ai-avatar {
  flex: none; width: 22px; height: 22px; border-radius: 50%; background: #1f6feb; color: #fff;
  display: inline-flex; align-items: center; justify-content: center; font-size: 10px; font-weight: 700;
}
.pr-head .title { color: var(--fg-secondary); }
.pr-head .title strong { color: var(--fg-default); }
.pr-head .title code { font-family: var(--mono); color: var(--fg-secondary); background: none; border: none; padding: 0; }
.pr-stats { margin-left: auto; font-family: var(--mono); font-size: 12px; }
.pr-stats .add { color: var(--success-fg); }
.pr-stats .del { color: var(--danger-fg); }
.diff { background: var(--bg-canvas); font-family: var(--mono); line-height: 1.9; overflow-x: auto; }
.diff-row { display: flex; white-space: pre; }
.diff-row .ln {
  flex: none; width: 40px; padding-right: 10px; text-align: right;
  color: var(--fg-subtle); user-select: none;
}
.diff-row .code { flex: 1; padding-right: 12px; }
.diff-row.add { background: var(--diff-add-bg); }
.diff-row.add .code { color: var(--fg-default); }
.diff-row.del { background: var(--diff-del-bg); }
.diff-row .sign-add { color: var(--success-fg); }
.diff-row .sign-del { color: var(--danger-fg); }
.kw { color: #ff7b72; }
.fn { color: #d2a8ff; }

.article details {
  border: 1px solid var(--border-default); border-radius: 8px;
  background: var(--bg-card); padding: 12px 16px; margin: 0 0 16px;
}
.article details summary { cursor: pointer; color: var(--fg-default); font-weight: 600; }
.article details p { margin-top: 12px; }

/* Article CTA box */
.cta-box {
  border: 1px solid var(--border-default); border-radius: 10px; background: var(--bg-inset);
  padding: 22px 24px; margin: 36px 0 0;
}
.cta-box p { margin: 0 0 14px; color: var(--fg-secondary); }
.article-foot { max-width: 720px; margin: 0 auto; padding: 0 32px 72px; }
.article-foot a.back { font-size: 14px; }

@media (max-width: 600px) {
  .wrap { padding: 0 20px; }
  .site-nav { gap: 14px; }
  .site-nav .hide-sm { display: none; }
  .article { padding: 40px 20px 32px; }
  .article h1 { font-size: 27px; }
  .article-foot { padding: 0 20px 56px; }
}