:root {
  color-scheme: light;
  --max-width: 720px;
  --fg: #222;
  --muted: #666;
  --border: #ddd;
  --link: #0a5cb8;
  --bg-code: #f5f5f5;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", Meiryo, sans-serif;
  color: var(--fg);
  line-height: 1.8;
  background: #fff;
}
header.site-header, footer.site-footer {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1rem 1.25rem;
}
header.site-header {
  border-bottom: 1px solid var(--border);
}
header.site-header a.brand {
  font-weight: bold;
  font-size: 1.1rem;
  color: var(--fg);
  text-decoration: none;
}
header.site-header nav {
  margin-top: 0.5rem;
  font-size: 0.9rem;
}
header.site-header nav a {
  margin-right: 1rem;
  color: var(--link);
  text-decoration: none;
}
main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.25rem 1.25rem 2rem;
}
h1 { font-size: 1.5rem; line-height: 1.4; }
h2 { font-size: 1.25rem; margin-top: 2.2rem; border-left: 4px solid var(--link); padding-left: 0.5rem; }
h3 { font-size: 1.05rem; margin-top: 1.5rem; }
p, li { font-size: 0.98rem; }
a { color: var(--link); }
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1rem 0;
  font-size: 0.9rem;
  display: block;
  overflow-x: auto;
  white-space: nowrap;
}
th, td {
  border: 1px solid var(--border);
  padding: 0.5rem 0.6rem;
  text-align: left;
  white-space: normal;
}
th { background: #fafafa; }
pre {
  background: var(--bg-code);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1rem;
  overflow-x: auto;
  font-size: 0.85rem;
  white-space: pre-wrap;
  word-break: break-word;
}
code { font-family: SFMono-Regular, Consolas, "Liberation Mono", monospace; }
blockquote {
  margin: 1rem 0;
  padding: 0.6rem 1rem;
  border-left: 4px solid #e0a800;
  background: #fff8e6;
  color: #444;
  font-size: 0.92rem;
}
.notice {
  margin-top: 2.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border);
  font-size: 0.85rem;
  color: var(--muted);
}
.meta {
  color: var(--muted);
  font-size: 0.85rem;
}
.article-list li {
  margin-bottom: 1rem;
}
.article-list .date {
  color: var(--muted);
  font-size: 0.85rem;
}
.ad-slot {
  margin: 1.5rem 0;
  padding: 0.75rem;
  border: 1px dashed var(--border);
  color: var(--muted);
  font-size: 0.8rem;
  text-align: center;
}
@media (max-width: 480px) {
  h1 { font-size: 1.3rem; }
  h2 { font-size: 1.1rem; }
}