.reference-hero {
  padding-top: clamp(70px, 10vw, 136px);
  padding-bottom: clamp(62px, 9vw, 120px);
  border-bottom: 1px solid var(--color-border);
  background:
    radial-gradient(circle at 86% 12%, var(--color-sand-haze), var(--color-sand-clear) 34%),
    radial-gradient(circle at 8% 82%, var(--color-soft-haze), var(--color-soft-clear) 31%),
    var(--color-bg);
}

.reference-hero h1 {
  max-width: 720px;
  font-size: clamp(34px, 3.35vw, 48px);
}

.reference-lead {
  max-width: 720px;
  margin-bottom: 28px;
  color: var(--color-text-muted);
  font-size: clamp(17px, 1.7vw, 21px);
  line-height: 1.75;
}

.reference-meta {
  display: flex;
  max-width: 100%;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 34px;
}

.reference-meta span {
  display: inline-flex;
  min-height: 32px;
  max-width: 100%;
  align-items: center;
  padding: 6px 13px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-bg);
  color: var(--color-text-muted);
  font: 12px/1.4 var(--font-mono);
}

.reference-intro {
  margin-top: 10px;
}

.reference-toc-section {
  padding-top: clamp(54px, 7vw, 92px);
  padding-bottom: clamp(54px, 7vw, 92px);
  background: var(--color-panel);
}

.reference-toc-head {
  max-width: 720px;
  margin-bottom: 32px;
}

.reference-toc-head h2 {
  margin-bottom: 14px;
}

.reference-toc-head p:last-child {
  color: var(--color-text-muted);
}

.reference-toc-section .jump-toc {
  border-color: var(--color-border);
}

.reference-article {
  background: var(--color-bg);
}

.chapter {
  scroll-margin-top: calc(var(--header-height) + 20px);
  padding-top: clamp(76px, 10vw, 136px);
  padding-bottom: clamp(76px, 10vw, 136px);
  border-bottom: 1px solid var(--color-border);
}

.chapter:nth-child(even) {
  background: var(--color-panel);
}

.chapter-index {
  margin-bottom: 18px;
  color: var(--color-accent);
  font: 600 12px/1.45 var(--font-mono);
  letter-spacing: .13em;
}

.chapter .prose > h2:first-of-type {
  margin-top: 0;
}

.chapter .prose h2 {
  margin-bottom: 34px;
}

.chapter .prose h3 {
  margin-top: 2.2em;
  font-family: var(--font-body);
  font-size: clamp(20px, 2vw, 25px);
}

.chapter .prose p {
  color: var(--color-text-muted);
  line-height: 1.88;
}

.chapter .prose strong {
  color: var(--color-text);
}

.chapter .data-table-wrap {
  margin-top: 34px;
  margin-bottom: 34px;
  border-radius: var(--radius-medium);
}

.chapter .data-table {
  min-width: 680px;
  font-size: 14px;
}

.chapter .data-table th {
  font-family: var(--font-body);
}

.chapter .data-table td {
  color: var(--color-text-muted);
}

.chapter pre {
  margin-top: 30px;
  margin-bottom: 30px;
  border: 1px solid var(--color-window-border);
  box-shadow: var(--shadow-window);
}

.chapter .callout {
  margin-top: 32px;
  margin-bottom: 32px;
}

.chapter .callout p {
  color: var(--color-text-muted);
}

.chapter .callout-title {
  color: var(--color-accent-dark);
}

.client-checklist {
  margin-top: 36px;
  margin-bottom: 36px;
  padding: clamp(24px, 4vw, 38px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-large);
  background: var(--color-bg);
}

.client-checklist h3 {
  margin-top: 0;
}

.client-checklist ol {
  margin-bottom: 0;
  padding-left: 24px;
}

.client-checklist li {
  padding-left: 6px;
  color: var(--color-text-muted);
}

.client-checklist li + li {
  margin-top: 12px;
}

@media (max-width: 768px) {
  .reference-hero h1 {
    font-size: clamp(26px, 8vw, 30px);
  }

  .reference-lead {
    font-size: 17px;
  }

  .reference-toc-section .jump-toc {
    border-radius: var(--radius-medium);
  }

  .chapter .prose h2 {
    margin-bottom: 28px;
  }
}

@media (max-width: 640px) {
  .reference-hero {
    padding-top: 56px;
    padding-bottom: 62px;
  }

  .reference-meta {
    gap: 8px;
  }

  .reference-meta span {
    font-size: 11px;
  }

  .reference-toc-section {
    padding-top: 52px;
    padding-bottom: 52px;
  }

  .chapter {
    padding-top: 72px;
    padding-bottom: 72px;
  }

  .chapter .prose p {
    line-height: 1.82;
  }

  .chapter .data-table {
    min-width: 620px;
  }

  .client-checklist {
    padding: 22px;
  }
}