#view-about { height: 100vh; height: 100dvh; min-height: 0; overflow: hidden; }
#view-about .hdr { flex: 0 0 auto; }
.about-page-main { flex: 1 1 auto; min-height: 0; overflow: auto; overscroll-behavior: contain; scrollbar-color: var(--line-board) var(--surface-panel-deep); }
.about-document { width: min(100%, 1260px); margin: 0 auto; padding: 32px max(32px, env(safe-area-inset-right)) max(40px, env(safe-area-inset-bottom)) max(32px, env(safe-area-inset-left)); }
.about-intro { padding-bottom: 28px; border-bottom: 1px solid var(--line-subtle); }
.about-intro h1 { margin: 10px 0; font-family: var(--font-display); font-size: 56px; font-weight: 400; line-height: 1.05; letter-spacing: .02em; color: var(--gold-050); }
#about-heading:focus { outline: none; }
.about-lead { margin: 0 0 18px; font-size: 23px; line-height: 1.4; color: var(--gold-100); }
.about-summary { max-width: 78ch; font-size: 18px; line-height: 1.65; color: var(--text-secondary); }
.about-entry { display: flex; align-items: center; flex-wrap: wrap; gap: 12px 20px; margin-top: 24px; }
.about-play-link, .about-rules-link { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; padding: 10px 22px; font-size: 18px; text-decoration: none; }
.about-static-note { margin-top: 20px; font-size: 16px; color: var(--text-secondary); }
.about-reading-layout { display: grid; grid-template-columns: 204px minmax(0, 1fr); gap: 32px; margin-top: 32px; }
.about-contents { position: sticky; top: 20px; align-self: start; display: grid; gap: 4px; padding: 18px; border: 1px solid var(--line-subtle); background: var(--surface-panel-deep); }
.about-contents > span { margin-bottom: 12px; }
.about-contents a { display: flex; align-items: center; min-height: 44px; padding: 8px 10px; font-size: 16px; line-height: 1.35; color: var(--text-secondary); text-decoration: none; border-left: 2px solid var(--line-subtle); }
.about-contents a:hover { color: var(--gold-100); border-left-color: var(--line-active); background: var(--surface-hover); }
.about-reading { min-width: 0; padding: 28px 32px; border: 1px solid var(--line-subtle); background: var(--surface-panel); }
.about-reading section { scroll-margin-top: 24px; }
.about-reading section + section { margin-top: 36px; padding-top: 28px; border-top: 1px solid var(--line-subtle); }
.about-section-label { margin-bottom: 12px; }
.about-reading h2 { margin: 0 0 18px; font-family: var(--font-display); font-size: 36px; font-weight: 400; line-height: 1.15; color: var(--gold-050); }
.about-reading h3 { margin: 0 0 8px; font-size: 21px; line-height: 1.3; color: var(--text-primary); }
.about-reading p { margin: 0 0 16px; font-size: 18px; line-height: 1.7; color: var(--text-secondary); }
.about-reading a { color: var(--gold-100); text-underline-offset: 3px; }
.about-note { margin-top: 24px; padding: 18px 20px; border-left: 2px solid var(--line-board); background: var(--surface-panel-deep); }
.about-note p { margin: 10px 0 0; font-size: 16px; }
.about-feature-list { margin: 20px 0; padding-left: 22px; font-size: 18px; line-height: 1.65; color: var(--text-primary); }
.about-feature-list li { padding: 4px 0; }
.about-basics { margin: 22px 0; border: 1px solid var(--line-subtle); padding: 0 18px; background: var(--surface-panel-deep); }
.about-basics ol { padding-left: 22px; margin: 0 0 18px; font-size: 17px; line-height: 1.6; color: var(--text-secondary); }
.about-basics li + li { margin-top: 12px; }
.about-credit-row + .about-credit-row { margin-top: 24px; }
.about-music-credits { padding: 0 18px; border: 1px solid var(--line-subtle); background: var(--surface-panel-deep); }
.about-music-credits ul { margin: 0; padding: 0 0 16px; list-style: none; }
.about-music-credits li { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr); gap: 3px 20px; padding: 12px 0; border-top: 1px solid var(--line-subtle); font-size: 17px; line-height: 1.5; }
.about-music-credits small { grid-column: 1 / -1; font-size: 13px; color: var(--text-muted); }
.about-question { border-bottom: 1px solid var(--line-subtle); }
.about-reading summary { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 56px; padding: 16px 0; cursor: pointer; font-size: 20px; line-height: 1.3; color: var(--text-primary); list-style: none; }
.about-reading summary::-webkit-details-marker { display: none; }
.about-reading summary::after { content: '+'; flex: 0 0 auto; font-family: var(--font-display); font-size: 28px; color: var(--gold-300); }
.about-reading details[open] > summary::after { content: '−'; }
.about-reading details[open] > summary { color: var(--gold-100); }
.about-question p { margin: 0; padding-bottom: 20px; }
.about-document-footer { display: flex; justify-content: space-between; align-items: center; gap: 20px; flex-wrap: wrap; margin-top: 36px; padding-top: 24px; border-top: 1px solid var(--line-board); }
.about-document-footer p { flex: 1 1 260px; margin: 0; font-size: 14px; }
.about-document-footer > a { display: inline-flex; align-items: center; min-height: 44px; padding: 10px 16px; font-size: 16px; text-decoration: none; }
#view-about :is(a, summary):focus-visible { outline: 2px solid var(--theme-focus); outline-offset: 3px; }
#view-about :is(main, section):focus-visible { outline: 2px solid var(--theme-focus); outline-offset: -2px; }
.about-info-link { display: inline-flex; align-items: center; justify-content: center; }
.about-menu-entry { text-decoration: none; }
.about-table-entry { display: inline-flex; align-items: center; min-height: 44px; margin-top: 12px; padding: 8px 16px; font-size: 15px; text-decoration: none; }
@media (min-width: 2200px) and (min-height: 1000px) {
  .about-document { width: min(100%, 1540px); padding-block: 40px 56px; }
  .about-intro h1 { font-size: 64px; }
  .about-reading-layout { grid-template-columns: 230px minmax(0, 1fr); gap: 40px; }
  .about-reading { padding: 36px 40px; }
  .about-summary, .about-reading p { font-size: 20px; }
}
@media (max-width: 1199px) {
  .about-document { padding: 24px max(20px, env(safe-area-inset-right)) 32px max(20px, env(safe-area-inset-left)); }
  .about-reading-layout { grid-template-columns: 170px minmax(0, 1fr); gap: 20px; }
  .about-contents { padding: 12px; }
  .about-reading { padding: 22px 24px; }
  .about-intro h1 { font-size: 46px; }
}
@media (max-width: 699px) {
  .about-document { padding-inline: max(12px, env(safe-area-inset-left)) max(12px, env(safe-area-inset-right)); padding-top: 20px; }
  .about-intro h1 { font-size: 40px; }
  .about-lead { font-size: 20px; }
  .about-summary { font-size: 17px; }
  .about-entry { gap: 12px; }
  .about-entry > span { flex-basis: 100%; font-size: 11px; }
  .about-reading-layout { grid-template-columns: minmax(0, 1fr); gap: 16px; margin-top: 24px; }
  .about-contents { position: static; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 6px; }
  .about-contents > span { grid-column: 1 / -1; margin: 0 0 8px; }
  .about-contents a { font-size: 15px; }
  .about-reading { padding: 20px 16px; }
  .about-reading h2 { font-size: 30px; }
  .about-reading p, .about-feature-list { font-size: 17px; }
  .about-reading summary { font-size: 18px; }
  .about-note { padding: 16px; }
  .about-music-credits li { grid-template-columns: minmax(0, 1fr); }
}
@media (forced-colors: active) {
  .about-reading, .about-contents, .about-note, .about-basics, .about-music-credits { background: Canvas; color: CanvasText; border-color: CanvasText; }
  #view-about :is(a, summary):focus-visible { outline-color: Highlight; }
}