:root {
  color-scheme: light;
  --color-bg: #f7f3ef;
  --color-surface: #ffffff;
  --color-text: #2b2118;
  --color-muted: #6b5f55;
  --color-accent: #6f4e37;
  --color-border: #e6ddd4;
  --color-link: #5c3d2e;
  --font-sans: "Segoe UI", "Hiragino Sans", "Noto Sans JP", sans-serif;
  --max-width: 720px;
  --radius: 12px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 16px;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-sans);
  line-height: 1.7;
  color: var(--color-text);
  background: linear-gradient(180deg, #faf6f1 0%, var(--color-bg) 100%);
}

a {
  color: var(--color-link);
}

a:hover {
  text-decoration-thickness: 2px;
}

.site-header,
.site-footer {
  padding: 16px 20px;
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
}

.site-footer {
  border-top: 1px solid var(--color-border);
  border-bottom: none;
  margin-top: 48px;
  color: var(--color-muted);
  font-size: 0.875rem;
}

.site-header__inner,
.site-footer__inner,
.page-shell {
  max-width: var(--max-width);
  margin: 0 auto;
}

.site-brand {
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--color-accent);
  text-decoration: none;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 16px;
  margin-top: 10px;
  font-size: 0.9375rem;
}

.site-nav a {
  text-decoration: none;
}

.site-nav a[aria-current="page"] {
  font-weight: 700;
  text-decoration: underline;
}

.page-shell {
  padding: 28px 20px 40px;
}

.hero {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 24px;
}

.hero h1 {
  margin: 0 0 8px;
  font-size: 1.75rem;
  line-height: 1.3;
  color: var(--color-accent);
}

.hero p {
  margin: 0;
  color: var(--color-muted);
}

.card-grid {
  display: grid;
  gap: 16px;
}

.card {
  display: block;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px;
  text-decoration: none;
  color: inherit;
}

.card:hover {
  border-color: var(--color-accent);
}

.card h2 {
  margin: 0 0 8px;
  font-size: 1.125rem;
  color: var(--color-accent);
}

.card p {
  margin: 0;
  color: var(--color-muted);
  font-size: 0.9375rem;
}

.document h1 {
  margin: 0 0 12px;
  font-size: 1.75rem;
  line-height: 1.3;
  color: var(--color-accent);
}

.document h2 {
  margin: 28px 0 10px;
  font-size: 1.25rem;
  line-height: 1.4;
  color: var(--color-accent);
}

.document h3 {
  margin: 20px 0 8px;
  font-size: 1.0625rem;
  line-height: 1.4;
}

.document p {
  margin: 0 0 12px;
}

.document ul,
.document ol {
  margin: 0 0 12px;
  padding-left: 1.4rem;
}

.document li {
  margin-bottom: 6px;
}

.document li > ul,
.document li > ol {
  margin-top: 6px;
  margin-bottom: 0;
}

.document code {
  font-size: 0.875em;
  background: #f0ebe6;
  padding: 0.1em 0.35em;
  border-radius: 4px;
}

@media (min-width: 640px) {
  .hero h1,
  .document h1 {
    font-size: 2rem;
  }
}