:root {
  color-scheme: light dark;
  --text-color: #1a1a1a;
  --muted-color: #6b6b6b;
  --link-color: #0b5fff;
  --border-color: #e5e5e5;
  --max-width: 680px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0 20px;
  font-family: system-ui, -apple-system, "Segoe UI", "Hiragino Sans",
    "Yu Gothic", Meiryo, sans-serif;
  color: var(--text-color);
  background-color: #ffffff;
  line-height: 1.7;
}

header, main, footer {
  max-width: var(--max-width);
  margin: 0 auto;
}

header {
  padding: 60px 0 20px;
}

header h1 {
  font-size: 1.8rem;
  margin: 0 0 4px;
}

.subtitle {
  color: var(--muted-color);
  margin: 0;
  font-size: 0.95rem;
}

section {
  padding: 30px 0;
  border-top: 1px solid var(--border-color);
}

section h2 {
  font-size: 1.1rem;
  margin: 0 0 16px;
  color: var(--text-color);
}

.list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.list li {
  margin-bottom: 12px;
}

.list dt {
  font-weight: 600;
}

.list dd {
  margin: 0 0 12px;
}

.inline-dl {
  display: grid;
  grid-template-columns: max-content 1fr;
  column-gap: 12px;
  row-gap: 12px;
}

.inline-dl dd {
  margin: 0;
}

.list a {
  color: var(--link-color);
  text-decoration: none;
  font-weight: 500;
}

.list a:hover {
  text-decoration: underline;
}

.desc {
  margin: 4px 0 0;
  color: var(--muted-color);
  font-size: 0.9rem;
}

.links li {
  display: inline-block;
  margin-right: 16px;
}

footer {
  padding: 40px 0 60px;
  color: var(--muted-color);
  font-size: 0.85rem;
  border-top: 1px solid var(--border-color);
  margin-top: 20px;
}

footer p {
  margin: 0 0 8px;
}

footer p:last-child {
  margin-bottom: 0;
}

.disclaimer {
  font-size: 0.8rem;
}

/* ダークモード */
@media (prefers-color-scheme: dark) {
  :root {
    --text-color: #d4d4d4;
    --muted-color: #a0a0a0;
    --link-color: #7aa2ff;
    --border-color: #333;
  }
  body {
    background-color: #1c1c1e;
  }
}