:root {
  color-scheme: light dark;
  --ink: #16191c;
  --muted: #5d636a;
  --line: #e3e5e1;
  --paper: #fbfbf9;
  --accent: oklch(0.51 0.14 248);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Segoe UI", "Microsoft YaHei", sans-serif;
}
@media (prefers-color-scheme: dark) {
  :root { --ink: #eceee9; --muted: #a3a8ad; --line: #2b2f33; --paper: #121416; --accent: oklch(0.72 0.13 248); }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--paper); color: var(--ink); line-height: 1.7; font-size: 17px; }
a { color: var(--accent); }
main, header, footer { max-width: 720px; margin: 0 auto; padding: 0 24px; }
header { padding-top: 32px; }
header a { display: flex; align-items: center; gap: 10px; color: inherit; text-decoration: none; font-weight: 600; }
h1 { font-size: 2.1rem; line-height: 1.25; margin: 56px 0 12px; letter-spacing: -0.01em; }
h2 { font-size: 1.25rem; margin: 40px 0 8px; }
h3 { font-size: 1.05rem; margin: 24px 0 4px; }
.lede { font-size: 1.15rem; color: var(--muted); margin: 0 0 24px; }
.note { border-left: 3px solid var(--accent); padding: 4px 0 4px 14px; color: var(--muted); }
section + section { border-top: 1px solid var(--line); margin-top: 40px; }
ul { padding-left: 1.2em; }
footer { color: var(--muted); font-size: 0.9rem; padding-top: 48px; padding-bottom: 48px; }
footer nav { display: flex; flex-wrap: wrap; gap: 16px; }