:root {
  color-scheme: light dark;
  --bg: #f4f5fb;
  --surface: #ffffff;
  --text: #1a1c23;
  --muted: #5b5f6b;
  --line: #dfe2ec;
  --brand: #2b64ff;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #121419; --surface: #1c1f27; --text: #eceef4; --muted: #a3a8b5; --line: #2f3340; --brand: #8fb0ff; }
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", "Yu Gothic", sans-serif;
  line-height: 1.8; font-size: 16px;
}
header { padding: 28px 20px 8px; max-width: 720px; margin: 0 auto; }
header a { color: var(--text); text-decoration: none; font-weight: 700; display: inline-flex; align-items: center; gap: 10px; }
header a .mark { width: 28px; height: 28px; border-radius: 8px; background: var(--brand); display: inline-block; }
main { max-width: 720px; margin: 0 auto; padding: 8px 20px 48px; }
article { background: var(--surface); border-radius: 20px; padding: 28px 24px; }
h1 { font-size: 26px; line-height: 1.35; margin: 0 0 6px; }
h2 { font-size: 18px; margin: 32px 0 8px; }
p, li { color: var(--text); }
.meta { color: var(--muted); font-size: 14px; margin: 0 0 20px; }
a { color: var(--brand); }
table { width: 100%; border-collapse: collapse; font-size: 15px; margin: 8px 0 16px; }
th, td { text-align: left; vertical-align: top; padding: 10px 8px; border-bottom: 1px solid var(--line); }
th { color: var(--muted); font-weight: 600; white-space: nowrap; }
ol, ul { padding-left: 22px; }
.links { list-style: none; padding: 0; margin: 16px 0 0; }
.links li { margin: 0; border-top: 1px solid var(--line); }
.links li:first-child { border-top: 0; }
.links a { display: block; padding: 14px 4px; text-decoration: none; font-weight: 600; }
footer { max-width: 720px; margin: 0 auto; padding: 0 20px 40px; color: var(--muted); font-size: 13px; }
@media (max-width: 480px) { article { padding: 22px 18px; } h1 { font-size: 23px; } table { font-size: 14px; } th, td { padding: 8px 6px; } }