:root {
  --bg: #f7fafa;
  --fg: #12302d;
  --muted: #4b6865;
  --accent: #0f766e;
  --code-bg: #e6f2f1;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1716;
    --fg: #e3efed;
    --muted: #9db5b2;
    --accent: #5eead4;
    --code-bg: #1c2b29;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: system-ui, -apple-system, "Hiragino Sans", "Noto Sans JP", sans-serif;
  line-height: 1.75;
}

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 40px 16px 64px;
}

h1 { font-size: 1.8rem; line-height: 1.3; margin: 0.4em 0; }
h2 { font-size: 1.25rem; margin-top: 2em; border-bottom: 1px solid var(--code-bg); padding-bottom: 0.3em; }
a { color: var(--accent); }
code { background: var(--code-bg); padding: 0.1em 0.35em; border-radius: 4px; font-size: 0.92em; }
li { margin: 0.3em 0; }
.crumb, .meta, .note { color: var(--muted); font-size: 0.9rem; }
.app-icon { display: block; margin-top: 8px; }
.links { padding-left: 1.2em; }