:root {
  --handbook-lead-width: 760px;
  --handbook-toc-gap: 28px;
  --handbook-section-gap: 76px;
  --handbook-copy-gap: 18px;
  --handbook-step-size: 34px;
}

.handbook-hero {
  padding-top: clamp(52px, 8vw, 92px);
  padding-bottom: clamp(42px, 6vw, 72px);
  border-bottom: 1px solid var(--color-border);
}

.handbook-hero-copy {
  max-width: var(--handbook-lead-width);
}

.handbook-hero .eyebrow {
  margin-bottom: 18px;
}

.handbook-hero-lead {
  color: var(--color-text-muted);
  font-size: clamp(16px, 2vw, 19px);
}

.handbook-hero-note {
  margin-top: 24px;
  padding: 18px 20px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-panel);
  color: var(--color-text);
  box-shadow: var(--shadow-soft);
}

.handbook-hero-note p {
  color: var(--color-text-muted);
}

.handbook-layout {
  display: grid;
  gap: var(--handbook-toc-gap);
}

.handbook-layout .page-toc {
  top: 10px;
}

.handbook-article {
  width: 100%;
  max-width: var(--reading-width);
  margin-inline: auto;
}

.handbook-article > section {
  padding-top: var(--handbook-section-gap);
  scroll-margin-top: calc(var(--header-height) + 22px);
}

.handbook-article > section:first-child {
  padding-top: 18px;
}

.handbook-article h2 {
  margin-top: 0;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--color-border);
}

.handbook-article h3 {
  margin-top: 34px;
}

.handbook-article .callout,
.handbook-article .table-scroll,
.handbook-article pre {
  margin-top: 24px;
  margin-bottom: 28px;
}

.handbook-article .button-row {
  margin-top: 26px;
}

.handbook-summary {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 28px;
}

.handbook-summary-item {
  padding: 17px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg);
  color: var(--color-text);
  box-shadow: var(--shadow-soft);
}

.handbook-summary-item strong,
.handbook-summary-item span {
  display: block;
}

.handbook-summary-item strong {
  margin-bottom: 5px;
}

.handbook-summary-item span {
  color: var(--color-text-muted);
  font-size: 13px;
}

.sequence-list {
  display: grid;
  gap: 14px;
  padding: 0;
  list-style: none;
  counter-reset: handbook-sequence;
}

.sequence-list li {
  position: relative;
  min-height: var(--handbook-step-size);
  padding-left: 50px;
  counter-increment: handbook-sequence;
}

.sequence-list li::before {
  position: absolute;
  top: 1px;
  left: 0;
  display: grid;
  width: var(--handbook-step-size);
  height: var(--handbook-step-size);
  place-items: center;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-panel);
  color: var(--color-accent-dark);
  content: counter(handbook-sequence);
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 750;
}

.manual-path {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 22px 0;
  padding: 0;
  list-style: none;
}

.manual-path li {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 12px;
}

.manual-path li:not(:last-child)::after {
  color: var(--color-accent);
  content: "→";
}

.chapter-close {
  margin-top: 30px;
  padding-top: 20px;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
}

.related-reading {
  margin-top: 58px;
  padding: clamp(22px, 4vw, 32px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-panel);
  color: var(--color-text);
  box-shadow: var(--shadow-soft);
}

.related-reading p {
  color: var(--color-text-muted);
}

.related-reading-list {
  display: grid;
  gap: 10px;
  padding: 0;
  list-style: none;
}

.related-reading-list a {
  display: flex;
  min-height: 46px;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 10px 13px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  color: var(--color-text);
  font-weight: 650;
  text-decoration: none;
}

.related-reading-list a:hover {
  border-color: var(--color-accent);
  color: var(--color-accent-dark);
}

@media (max-width: 760px) {
  .handbook-summary {
    grid-template-columns: minmax(0, 1fr);
  }

  .handbook-article > section {
    padding-top: 58px;
  }

  .related-reading-list a {
    align-items: flex-start;
    flex-direction: column;
    gap: 3px;
  }
}