:root {
  --bg: #ffffff;
  --fg: #1c1c1e;
  --muted: #5c6470;
  --line: #e3e6ea;
  --accent: #38b6fe;
  --card: #f6f8fa;
  --warn-bg: #fff6e5;
  --warn-line: #f0b429;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171a;
    --fg: #e9edf1;
    --muted: #9aa4b2;
    --line: #2a2f36;
    --accent: #38b6fe;
    --card: #1c2126;
    --warn-bg: #2c2415;
    --warn-line: #b8860b;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", sans-serif;
  line-height: 1.9;
  font-size: 16px;
}
.wrap { max-width: 760px; margin: 0 auto; padding: 24px 20px 80px; }
header.site {
  background: var(--accent);
  color: #fff;
  padding: 28px 20px;
}
header.site .wrap { padding: 0; max-width: 760px; }
header.site a { color: #fff; text-decoration: none; }
header.site h1 { margin: 0; font-size: 1.35rem; letter-spacing: .02em; }
header.site p { margin: 4px 0 0; opacity: .9; font-size: .9rem; }
h2 { font-size: 1.15rem; margin: 2.2em 0 .6em; padding-bottom: .3em; border-bottom: 1px solid var(--line); }
h3 { font-size: 1rem; margin: 1.6em 0 .4em; }
p, li { font-size: .96rem; }
ul, ol { padding-left: 1.3em; }
a { color: #0a7ea4; }
@media (prefers-color-scheme: dark) { a { color: #6fd0ff; } }
.note {
  background: var(--warn-bg);
  border-left: 4px solid var(--warn-line);
  padding: 14px 16px;
  margin: 20px 0;
  border-radius: 6px;
}
.note strong { display: block; margin-bottom: .3em; }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 16px 18px;
  margin: 14px 0;
}
.card h3 { margin-top: 0; }
.meta { color: var(--muted); font-size: .85rem; }
nav.links { margin: 24px 0; }
nav.links a { display: block; padding: 12px 14px; border: 1px solid var(--line); border-radius: 10px; margin-bottom: 10px; text-decoration: none; color: var(--fg); }
nav.links a span { display: block; color: var(--muted); font-size: .85rem; }
footer { border-top: 1px solid var(--line); margin-top: 48px; padding-top: 16px; color: var(--muted); font-size: .85rem; }