/* One continuous background per chapter; colors alternate at chapter boundaries. */
@media screen {
  #document-content > .document-section[data-chapter] {
    --chapter-paper:#eef5ed;--chapter-accent:#32664e;--chapter-tint:#dcebd9;
    background:var(--chapter-paper);border-bottom-color:transparent;
  }
  #document-content > .document-section:is([data-chapter="2"],[data-chapter="4"],[data-chapter="6"],[data-chapter="8"]) {
    --chapter-paper:#fff5e6;--chapter-accent:#805d27;--chapter-tint:#f3e5c9;
  }
  #document-content > .document-section.hero {background:#143e32;}
  .chapter-boundary {
    display:flex;align-items:center;gap:14px;padding:16px 20px;margin:0 0 32px;
    border:1px solid color-mix(in srgb,var(--chapter-accent) 28%,transparent);
    border-top:4px solid var(--chapter-accent);border-radius:10px;
    background:var(--chapter-tint);color:var(--chapter-accent);
  }
  .chapter-boundary-number {font-size:12px;font-weight:800;letter-spacing:.06em;white-space:nowrap;}
  .chapter-boundary strong {font-size:18px;line-height:1.45;color:inherit;}
  .chapter-boundary-start {margin-left:auto;font-size:12px;white-space:nowrap;}
  #document-content .hero .chapter-boundary {background:#ffffff0c;border-color:#b9d5a550;color:#e4efd7;}
  .sidebar .nav-group[data-chapter] > p {border-left:3px solid #b8d39f;padding-left:9px;}
  .sidebar .nav-group:is([data-chapter="2"],[data-chapter="4"],[data-chapter="6"],[data-chapter="8"]) > p {border-left-color:#e5c18c;color:#e5cfaa;}
  #document-content > #glossary-reference {background:#f1f3f4;border-top:4px solid #9aa9ab;}
}
@media screen and (max-width:600px) {
  .chapter-boundary {gap:10px;padding:12px 14px;margin-bottom:24px;flex-wrap:wrap;}
  .chapter-boundary strong {font-size:16px;}
  .chapter-boundary-start {font-size:11px;}
}
@media print {.chapter-boundary {display:none;}}