:root {
  color-scheme: light;
  --background: #ffffff;
  --text: #222222;
  --muted: #666666;
  --primary: #a61e55;
  --language-accent: #2563a8;
  --border: #e5e5e5;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--background);
  color: var(--text);
  font-family:
    -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans JP',
    'Hiragino Kaku Gothic ProN', Meiryo, sans-serif;
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--primary);
  text-underline-offset: 0.18em;
}

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

a:focus-visible {
  border-radius: 4px;
  outline: 3px solid rgb(185 31 97 / 25%);
  outline-offset: 3px;
}

.site-header {
  border-bottom: 1px solid var(--border);
  background: var(--background);
}

.header-inner,
.page,
.footer-inner {
  width: min(100% - 40px, 760px);
  margin-inline: auto;
}

.header-inner {
  display: flex;
  min-height: 64px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  color: var(--text);
  font-size: 1.05rem;
  font-weight: 700;
  text-decoration: none;
}

.site-nav {
  display: flex;
  flex: 1;
  flex-wrap: wrap;
  align-items: center;
  gap: 18px;
  font-size: 0.9rem;
}

.site-nav a {
  color: var(--muted);
  text-decoration: none;
  white-space: nowrap;
}

.site-nav a[aria-current='page'] {
  color: var(--text);
  font-weight: 700;
}

.site-nav .language-switch {
  display: inline-flex;
  align-items: center;
  margin-left: auto;
  gap: 0.4em;
  padding: 2px 9px;
  border: 1px solid #d6d6d6;
  border-radius: 999px;
  background: #f7f7f7;
  color: var(--text);
  font-size: 0.86em;
  font-weight: 600;
  line-height: 1.7;
  transition:
    border-color 160ms ease,
    background-color 160ms ease,
    color 160ms ease;
}

.site-nav .language-switch::before {
  content: '\1f310';
  font-size: 0.95em;
  line-height: 1;
}

.site-nav .language-switch:hover {
  border-color: var(--language-accent);
  background: #f2f7fc;
  color: var(--language-accent);
}

.page {
  padding-block: 56px 80px;
}

.document-header {
  margin-bottom: 48px;
}

h1,
h2 {
  line-height: 1.45;
}

h1 {
  margin: 0 0 12px;
  font-size: clamp(1.9rem, 6vw, 2.5rem);
  letter-spacing: -0.025em;
}

.lead {
  max-width: 680px;
  margin: 0;
  color: var(--muted);
}

.updated-at {
  display: block;
  margin-top: 16px;
  color: var(--muted);
  font-size: 0.82rem;
}

.document {
  padding: 0;
}

.document section + section {
  margin-top: 40px;
  padding-top: 36px;
  border-top: 1px solid var(--border);
}

h2 {
  margin: 0 0 16px;
  font-size: 1.25rem;
  letter-spacing: -0.01em;
}

p,
ul,
ol {
  margin-block: 0 1em;
}

p:last-child,
ul:last-child,
ol:last-child {
  margin-bottom: 0;
}

ul,
ol {
  padding-left: 1.4em;
}

li + li {
  margin-top: 0.45em;
}

.note {
  margin-top: 18px;
  padding: 14px 16px;
  border-left: 3px solid #cccccc;
  background: #f7f7f7;
}

.site-footer {
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.85rem;
}

.footer-inner {
  display: flex;
  min-height: 90px;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.footer-inner p {
  margin: 0;
}

@media (max-width: 560px) {
  .header-inner,
  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
  }

  .header-inner {
    padding-block: 14px;
    gap: 10px;
  }

  .footer-inner {
    padding-block: 24px;
    gap: 6px;
  }

  .site-nav {
    width: 100%;
    justify-content: flex-start;
    column-gap: 18px;
    row-gap: 8px;
  }

  .page {
    padding-block: 40px 56px;
  }
}

@media print {
  body {
    background: white;
    font-size: 11pt;
  }

  .site-header,
  .site-footer {
    display: none;
  }

  .page {
    width: 100%;
    padding: 0;
  }

  .document {
    padding: 0;
    border: 0;
    box-shadow: none;
  }

  .document section + section {
    break-inside: avoid;
  }
}