/* 长文沿着一条窄版心展开，章节号留在页边。 */
.about-page .page-intro { max-width: 48rem; }
.about-layout { display: grid; grid-template-columns: minmax(0, 12rem) minmax(0, 40rem); gap: 3.5rem; align-items: start; }
.about-contents { padding-top: 0.375rem; font: 0.75rem/1.8 var(--font-sans); color: var(--page-muted); }
.about-contents p { margin: 0 0 0.75rem; font-size: 0.625rem; letter-spacing: 0.12em; }
.about-contents ol { padding: 0; margin: 0; list-style: none; }
.about-contents li { margin-bottom: 0.75rem; }
.about-contents a { text-decoration: none; }
.about-contents a:hover { text-decoration: underline; }
.prose { min-width: 0; max-width: 40rem; line-height: 2; }
.prose p { margin: 0 0 1.25rem; }
.prose .opening { font-size: 1.1875rem; line-height: 2; }
.prose section { border-top: 1px solid var(--page-line); margin-top: 2.75rem; padding-top: 1.5rem; scroll-margin-top: 2rem; }
.prose h2 { margin: 0 0 1rem; font-size: 1.375rem; font-weight: 500; letter-spacing: 0.025em; }
.prose h2 span { display: inline-block; min-width: 2rem; color: var(--page-muted); font: 0.6875rem/1.8 var(--font-sans); vertical-align: middle; }
.prose ul { padding-left: 1.25rem; margin: 0; }
.prose li { padding-left: 0.25rem; margin: 0 0 0.875rem; }
.source-list { list-style: none; padding-left: 0 !important; }
.source-list li { display: grid; grid-template-columns: 5rem minmax(0, 1fr); gap: 1rem; padding: 0; margin-bottom: 1.25rem; }
.source-list .source-name { font: 0.75rem/2 var(--font-sans); color: var(--page-muted); padding-top: 0.125rem; }
.source-list .source-detail { font-size: 0.9375rem; overflow-wrap: anywhere; }
.about-ending { color: var(--page-muted); font-size: 0.875rem; }
@media (max-width: 900px) {
  .about-layout { grid-template-columns: minmax(0, 1fr); gap: 2.5rem; max-width: 43rem; }
  .about-contents ol { display: flex; flex-wrap: wrap; gap: 0.5rem 1.5rem; }
  .about-contents li { margin: 0; }
}
@media (max-width: 480px) {
  .prose { font-size: 0.9375rem; }
  .prose .opening { font-size: 1.0625rem; }
  .source-list li { grid-template-columns: 1fr; gap: 0.25rem; }
  .source-list .source-detail { font-size: 0.875rem; }
}