/* ALDA surface hierarchy: flat cards, raised shelves, floating controls, overlays. */
:root {
  --alda-card-edge: rgba(34,34,34,.10);
  --alda-shadow-card: 0 4px 16px rgba(34,34,34,.05);
  --alda-shadow-hover: 0 8px 24px rgba(34,34,34,.08);
  --alda-shadow-float: 0 8px 28px rgba(34,34,34,.10);
  --alda-shadow-nav: 0 2px 8px rgba(34,34,34,.05);
  --alda-shadow-overlay: 0 16px 48px rgba(34,34,34,.14);
}
/* Inset hairlines retain existing grid dimensions and card padding. */
body .ac-card, body .pc, body .hm-pcard, body .v2-card {
  background-color:var(--alda-paper);
  box-shadow:inset 0 0 0 1px var(--alda-card-edge);
  border-radius:12px;
  backdrop-filter:none;
}
body .pl-related .ac-card { box-shadow:inset 0 0 0 1px var(--alda-card-edge); }
body .shelf-scene-card, body .edit-story-card {
  background:var(--alda-paper);
  border:1px solid var(--alda-card-edge);
  border-radius:12px;
  box-shadow:var(--alda-shadow-card);
  backdrop-filter:none;
}
body .shelf-scene-card { transition:box-shadow .2s ease,border-color .2s ease; }
/* Leave the carousel's perspective transforms in control of positioning. */
@media(hover:hover) and (pointer:fine) {
  body .shelf-scene-window:not(.is-dragging) .shelf-scene-card:hover {
    box-shadow:var(--alda-shadow-hover);
    border-color:rgba(34,34,34,.16);
  }
}
body .shelf-scene-window.is-dragging .shelf-scene-card {
  box-shadow:var(--alda-shadow-card);
  border-color:var(--alda-card-edge);
  transition:none;
}
body .shelf-scene-card:focus-visible { outline:2px solid var(--alda-ink);outline-offset:3px; }
body .nav-expand:not(.is-open) .nav-study-actions,
body .pl-dock .pl-dock-in, body .ac-buybar,
body .pf-wrap.is-stuck .pf-bar, body .pf-float {
  box-shadow:var(--alda-shadow-float);
  border:1px solid var(--alda-card-edge);
  backdrop-filter:none;
  -webkit-backdrop-filter:none;
}
body .pl-dock .pl-dock-in, body .pf-wrap.is-stuck .pf-bar {
  background:var(--alda-paper);
}
body .nav-expand:not(.is-open) .nav-study-actions {
  box-shadow:var(--alda-shadow-nav);
}
body .nav-expand.is-open .nav-study-surface,
body .pf-sortmenu, body .pf-panel.is-drop, body .pf-panel.is-sheet {
  background:var(--alda-paper);
  border:1px solid var(--alda-card-edge);
  box-shadow:var(--alda-shadow-overlay);
}
body .nav-study-panel, body .ac-drawer { background:var(--alda-paper); }
body.ac-open .ac-drawer, html body[data-nav-concept].ac-open .ac-drawer { box-shadow:var(--alda-shadow-overlay);border-left:1px solid var(--alda-card-edge); }
body .nav-study-backdrop, body .ac-scrim, body[data-nav-concept] .ac-scrim {
  background:rgba(34,34,34,.20);
  backdrop-filter:blur(5px);
  -webkit-backdrop-filter:blur(5px);
}
@media(prefers-reduced-motion:reduce) {
  body .shelf-scene-card { transition:none; }
}