:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --fg: #111111;
  --muted: #666666;
  --line: #e5e5e5;
  --accent: #000000;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --fg: #f2f2f2;
    --muted: #9a9a9a;
    --line: #262626;
    --accent: #ffffff;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  padding: 0 20px 80px;
  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;
}

main { max-width: 720px; margin: 0 auto; }

header {
  padding: 48px 0 24px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 32px;
}

.wordmark {
  font-size: 32px;
  font-weight: 900;
  letter-spacing: -0.02em;
  text-decoration: none;
  color: var(--fg);
}

h1 { font-size: 26px; margin: 24px 0 8px; }
h2 { font-size: 18px; margin: 36px 0 8px; }
.updated { color: var(--muted); font-size: 14px; margin-top: 0; }
ul { padding-left: 1.3em; }
a { color: var(--fg); }

.contact {
  margin-top: 40px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 12px;
}

.nav { margin-top: 48px; padding-top: 24px; border-top: 1px solid var(--line); }
.nav a { margin-right: 20px; }

footer { margin-top: 56px; color: var(--muted); font-size: 14px; }