.content-layers {
  border-top: 1px solid var(--line);
  margin: 4px 0 24px;
}

.content-layer {
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.content-layer strong {
  display: block;
  font-size: 12px;
  font-weight: 500;
  color: var(--ink);
}

.content-layer p {
  margin: 5px 0 0;
  font-size: 11px;
  line-height: 1.8;
  color: var(--muted);
}

.reading-guide {
  margin: 0 0 28px;
  padding: 0 0 20px;
  border-bottom: 1px solid var(--reader-line, var(--line));
  color: var(--reader-muted, var(--muted));
  font: 12px/1.85 var(--sans);
}
#book-detail > .reading-guide { margin: 20px 24px; }
.reading-kind { color: var(--reader-accent, var(--accent)); margin-bottom: 6px; }
.reading-scope-details { margin-top: 10px; }
.reading-scope-details summary { cursor: pointer; padding-block: 6px; }
.reading-scope-details p { margin: 8px 0; }
.reading-scope-details strong { font-weight: 500; color: var(--reader-ink, var(--ink)); }
.related-reading { display: flex; flex-wrap: wrap; gap: 0 18px; margin-top: 12px; }
.related-reading > span { flex-basis: 100%; font-size: 11px; }
.related-reading button { padding: 9px 0; color: var(--reader-accent, var(--accent)); font-size: 12px; min-height: 40px; text-align: left; }
.related-reading button:hover { text-decoration: underline; text-underline-offset: 4px; }
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}