:root {
  --bg: #1a1614;
  --ink: #f5f0e6;
  --kinari: #d9c8a3;
  --shu: #c93f2c;
  --kincha: #b88f4a;
  --nezumi: #6f6a64;
  --line: rgba(245, 240, 230, 0.18);
  --washi-card: rgba(245, 240, 230, 0.04);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, "Hiragino Mincho ProN", "Yu Mincho", "YuMincho", "ヒラギノ明朝 ProN", serif;
  line-height: 1.85;
  font-size: 16px;
  letter-spacing: 0.02em;
}

body {
  max-width: 760px;
  margin: 0 auto;
  padding: 56px 24px 96px;
}

header {
  border-bottom: 1px solid var(--line);
  padding-bottom: 28px;
  margin-bottom: 36px;
}

h1 {
  font-size: 28px;
  margin: 0 0 8px;
  letter-spacing: 0.18em;
  font-weight: 600;
}

.brand-en {
  display: inline-block;
  margin-left: 14px;
  font-size: 15px;
  letter-spacing: 0.18em;
  color: var(--kinari);
  font-weight: 400;
  vertical-align: middle;
}

.tagline {
  color: var(--kinari);
  font-size: 14px;
  margin: 0;
}

h2 {
  font-size: 20px;
  margin: 44px 0 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
  letter-spacing: 0.06em;
  color: var(--ink);
  font-weight: 600;
}

h3 {
  font-size: 16px;
  margin: 28px 0 10px;
  color: var(--kincha);
  letter-spacing: 0.06em;
  font-weight: 600;
}

p, li {
  color: var(--ink);
  font-size: 14.5px;
}

ul, ol {
  padding-left: 22px;
}

li {
  margin: 6px 0;
}

a {
  color: var(--kincha);
  text-decoration: none;
  border-bottom: 1px solid rgba(184, 143, 74, 0.4);
}

a:hover {
  color: var(--shu);
  border-bottom-color: var(--shu);
}

.meta {
  color: var(--nezumi);
  font-size: 12px;
  margin-bottom: 32px;
}

.notice {
  background: var(--washi-card);
  border-left: 2px solid var(--shu);
  padding: 14px 18px;
  font-size: 13.5px;
  margin: 20px 0;
  color: var(--kinari);
}

.contact {
  display: inline-block;
  font-size: 16px;
  letter-spacing: 0.04em;
}

.links {
  display: flex;
  flex-wrap: wrap;
  gap: 14px 24px;
  margin-bottom: 32px;
}

.links a {
  font-size: 14px;
  letter-spacing: 0.04em;
}

.toc {
  background: var(--washi-card);
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 16px 22px;
  margin: 24px 0 36px;
}

.toc ol { padding-left: 18px; margin: 0; }
.toc li { margin: 4px 0; font-size: 13.5px; }

footer {
  margin-top: 64px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
  color: var(--nezumi);
  text-align: center;
}

.lang-switch {
  font-size: 12px;
  color: var(--nezumi);
  margin-bottom: 24px;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #fbf7ef;
    --ink: #2a2622;
    --kinari: #6a5e48;
    --line: rgba(42, 38, 34, 0.14);
    --washi-card: rgba(42, 38, 34, 0.04);
  }
}