:root {
  color-scheme: light dark;
  --bg: #f7f5f1;
  --fg: #2b2b2b;
  --muted: #6d675e;
  --rule: #ddd7cd;
  --link: #3f6f88;
  --accent: #c0392b;
  --code-bg: #efece6;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1a1a1f;
    --fg: #e8e6e1;
    --muted: #9a938a;
    --rule: #34343c;
    --link: #6ba3c7;
    --accent: #e74c3c;
    --code-bg: #24242b;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.7 -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC",
        "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
}
.wrap { max-width: 44rem; margin: 0 auto; padding: 0 1.25rem; }
a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }
header {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; padding: 1.5rem 0 0;
}
/* **logo 要看得清**（用户反馈 ✓）：176px 时副标 `YANSHI.WANGDA.TODAY` 只有几像素高 ✗
   ⇒ 桌面 280px ✓、窄屏 200px ✓（两个 logo 的 viewBox 是 420×160 与 560×180 ✓，等比缩放 ✓）。 */
header .brand img { display: block; width: 280px; height: auto; }
@media (max-width: 34rem) {
  header .brand img { width: 200px; }
}
header .brand .for-dark { display: none; }
@media (prefers-color-scheme: dark) {
  header .brand .for-light { display: none; }
  header .brand .for-dark { display: block; }
}
header nav { font-size: 0.9rem; white-space: nowrap; }
h1 { font-size: 1.6rem; line-height: 1.3; margin: 2.5rem 0 0.75rem; font-weight: 600; }
h2 {
  font-size: 1.05rem; font-weight: 600; margin: 2.25rem 0 0.5rem;
  padding-top: 1.25rem; border-top: 1px solid var(--rule);
}
p { margin: 0.6rem 0; }
.lede { font-size: 1.05rem; color: var(--fg); }
ul { padding-left: 1.15rem; margin: 0.6rem 0; }
li { margin: 0.45rem 0; }
.muted { color: var(--muted); }
small { color: var(--muted); }
code, pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  font-size: 0.875em;
}
pre {
  background: var(--code-bg); padding: 0.9rem 1rem; border-radius: 6px;
  overflow-x: auto; line-height: 1.6;
}
code { background: var(--code-bg); padding: 0.1em 0.35em; border-radius: 4px; }
pre code { background: none; padding: 0; }
.links { list-style: none; padding: 0; }
.links li { margin: 0.5rem 0; }
footer {
  margin: 3rem 0 0; padding: 1.25rem 0 2.5rem;
  border-top: 1px solid var(--rule); font-size: 0.875rem; color: var(--muted);
}
footer a { color: var(--muted); text-decoration: underline; }