:root { --fg: #111; --sub: #555; --line: #ddd; --bg: #fff; }
@media (prefers-color-scheme: dark) { :root { --fg: #eee; --sub: #aaa; --line: #333; --bg: #111; } }
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--fg);
  font-family: -apple-system, "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;
  font-size: 18px; line-height: 1.85; -webkit-text-size-adjust: 100%; }
main { max-width: 720px; margin: 0 auto; padding: 32px 20px 64px; }
header { border-bottom: 1px solid var(--line); }
header div { max-width: 720px; margin: 0 auto; padding: 16px 20px; }
header a { color: var(--fg); text-decoration: none; font-weight: 700; font-size: 20px; }
h1 { font-size: 28px; line-height: 1.4; margin: 8px 0 24px; }
h2 { font-size: 20px; margin: 40px 0 8px; }
p, li { margin: 0 0 12px; }
ul { padding-left: 1.4em; }
a { color: inherit; }
.date { color: var(--sub); font-size: 15px; }
.lead { font-size: 20px; }
nav ul { list-style: none; padding: 0; margin: 32px 0 0; border-top: 1px solid var(--line); }
nav li { margin: 0; border-bottom: 1px solid var(--line); }
nav a { display: block; padding: 16px 4px; text-decoration: none; }
dl { margin: 0; }
dt { font-weight: 700; margin-top: 16px; }
dd { margin: 0; }
footer { max-width: 720px; margin: 0 auto; padding: 24px 20px 48px; color: var(--sub); font-size: 15px; border-top: 1px solid var(--line); }
footer a { margin-right: 16px; }