/* BAND-002356 (UI-14): the Library station (js/library-station.js). A media-library catalogue:
   a toolbar of search and filters, a responsive grid of cards with a 16:9 preview (1 column on a
   phone, up to 4 on a wide stage) or a compact list, and the open item beside the catalogue from
   the lg breakpoint (in its place below it). Colours, spacing and type are tokens only. */

.library-station { display: grid; gap: var(--space-4); font-variant-numeric: tabular-nums; }
.library-station .section-heading { margin-bottom: 0; flex-wrap: wrap; }
.library-heading-actions { gap: var(--space-2); }
.library-view-switch { display: inline-flex; gap: var(--space-1); padding: var(--space-0-5); border: 1px solid var(--color-divider); border-radius: var(--radius-sm); background: var(--color-surface-2); }
/* The options of a segmented switch keep the small radius inside it (BAND-002877). */
.library-view-switch button.compact { min-width: 64px; border-radius: var(--radius-sm); }
/* The view in use: the brand's selected fill with the accent edge and a heavier weight, never the
   primary fill, which marks the one primary action (brand D-11). */
.library-view-switch button.compact[aria-pressed="false"]:enabled { font-weight: var(--font-weight-regular); }
.library-view-switch button.compact[aria-pressed="true"]:enabled { border-color: var(--color-accent); background: var(--color-selected); color: var(--color-text); }

/* ---- Toolbar ------------------------------------------------------------------------------ */
.library-filters {
  display: grid;
  grid-template-columns: minmax(0, 2fr) repeat(4, minmax(0, 1fr));
  gap: var(--space-3);
  align-items: start;
  padding: var(--space-3) var(--space-3-5);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
  background: var(--color-surface-2);
}
.library-filter { min-width: 0; }
.library-filter label { margin: 0 0 var(--space-1); }
.library-filter .field-hint { margin-top: var(--space-1); }
.library-search-box { position: relative; }
.library-search-box .icon { position: absolute; top: 50%; left: var(--space-3); width: 16px; height: 16px; color: var(--color-text-muted); transform: translateY(-50%); pointer-events: none; }
.library-filters input[type=search] {
  display: block;
  width: 100%;
  min-width: 0;
  min-height: var(--size-control);
  padding: var(--space-2) var(--space-3) var(--space-2) var(--space-9);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  color: var(--color-text);
  font-size: var(--font-size-sm);
  transition: border-color var(--motion-duration-short) var(--motion-easing-standard), box-shadow var(--motion-duration-short) var(--motion-easing-standard);
}
.library-filters input[type=search]:hover { border-color: var(--color-border-strong); }
/* BAND-002877: the toolbar is a dense row of compact controls, so its search and filters take sm
   (the brand's size for dense controls); at md the filter values no longer fit their columns. */
.library-filters select { min-height: var(--size-control); padding-top: var(--space-2); padding-bottom: var(--space-2); font-size: var(--font-size-sm); }

.library-summary { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2); min-height: 29px; }
.library-count { margin: 0; color: var(--color-text-muted); font-size: var(--font-size-sm); font-variant-numeric: tabular-nums; }
.library-count:empty { display: none; }
.library-source-chip { display: inline-flex; align-items: center; gap: var(--space-1); padding: 0 0 0 var(--space-2-5); border: 1px solid var(--color-info-border); border-radius: var(--radius-pill); background: var(--color-info-subtle); color: var(--color-info); font-size: var(--font-size-xs); font-weight: var(--font-weight-semibold); }
.library-source-chip[hidden] { display: none; }
.library-source-chip button.ghost.compact { min-height: 24px; padding: 0 var(--space-1-5); border-radius: var(--radius-pill); color: var(--color-info); }
.library-source-chip .icon { width: 14px; height: 14px; }

/* ---- Catalogue ------------------------------------------------------------------------------ */
.library-layout { display: grid; gap: var(--space-4); align-items: start; min-width: 0; }
.library-results {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(max(220px, calc((100% - 3 * var(--space-4)) / 4)), 1fr));
  gap: var(--space-4);
  margin: 0;
  padding: 0;
  list-style: none;
  min-width: 0;
}
.library-results[hidden] { display: none; }
.library-tile { min-width: 0; }
.library-tile-card {
  position: relative;
  display: grid;
  grid-template-rows: auto 1fr;
  height: 100%;
  overflow: hidden;
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-md);
  background: var(--color-surface);
  box-shadow: var(--shadow-xs);
  transition: border-color var(--motion-duration-short) var(--motion-easing-standard), box-shadow var(--motion-duration-short) var(--motion-easing-standard), transform var(--motion-duration-short) var(--motion-easing-standard);
}
.library-tile-card:hover { border-color: var(--color-divider-strong); box-shadow: var(--shadow-md); }
.library-tile-card:focus-within { border-color: var(--color-focus); }
/* BAND-002877: the halo only for pointer focus; with the keyboard the title draws the ring. */
.library-tile-card:focus-within:not(:has(:focus-visible)) { box-shadow: var(--shadow-focus-halo); }
.library-tile[data-selected="true"] .library-tile-card { border-color: var(--color-accent); outline: 1px solid var(--color-accent); outline-offset: -2px; box-shadow: var(--shadow-sm); }

.library-preview {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--color-surface-3);
}
.library-placeholder {
  position: absolute;
  inset: 0;
  display: grid;
  place-content: center;
  justify-items: center;
  gap: var(--space-1-5);
  color: var(--color-text-muted);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  background-color: var(--color-surface-2);
  background-image:
    radial-gradient(circle at 20% 15%, var(--color-accent-subtle), transparent 60%),
    linear-gradient(160deg, var(--color-surface-2), var(--color-surface-3));
}
.library-preview[data-cover="loaded"] .library-placeholder { visibility: hidden; }
.library-glyph { width: 32px; height: 32px; fill: none; stroke: currentcolor; stroke-width: 1.6; stroke-linecap: round; stroke-linejoin: round; }
.library-preview.is-large .library-glyph { width: 44px; height: 44px; }
.library-cover { position: absolute; inset: 0; width: 100%; height: 100%; object-fit: cover; background: var(--color-media); color: var(--color-text-on-media); }
.library-preview[data-cover="loading"] .library-cover { opacity: 0; }
.library-preview .library-status { position: absolute; top: var(--space-2); left: var(--space-2); box-shadow: var(--shadow-xs); }

.library-tile-body { display: grid; align-content: start; gap: var(--space-1); min-width: 0; padding: var(--space-3) var(--space-3-5) var(--space-3-5); }
.library-kind { margin: 0; color: var(--color-accent); font-size: var(--font-size-xs); font-weight: var(--font-weight-semibold); }
.library-tile-title { margin: 0; font-size: var(--font-size-md); line-height: var(--line-height-snug); }
button.library-open {
  display: block;
  min-height: 0;
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--color-text);
  font-size: inherit;
  font-weight: var(--font-weight-semibold);
  line-height: inherit;
  text-align: left;
  overflow-wrap: anywhere;
}
button.library-open:hover:not(:disabled) { background: transparent; color: var(--color-accent); }
/* The whole card is the target of its title button (one tab stop per card). */
button.library-open::after { content: ""; position: absolute; inset: 0; z-index: var(--z-raised); border-radius: var(--radius-md); }
button.library-open:focus-visible { outline: none; }
.library-tile-topic { margin: 0; color: var(--color-text-muted); font-size: var(--font-size-sm); line-height: var(--line-height-normal); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; overflow-wrap: anywhere; }
.library-tile-meta { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: var(--space-1-5) var(--space-2); margin-top: var(--space-1-5); }
.library-platforms { display: flex; flex-wrap: wrap; gap: var(--space-1); min-width: 0; }
.library-chip { display: inline-block; padding: 0 var(--space-1-5); border: 1px solid var(--color-divider-strong); border-radius: var(--radius-sm); color: var(--color-text-muted); font-size: var(--font-size-xs); line-height: var(--line-height-normal); white-space: nowrap; }
.library-date { color: var(--color-text-muted); font-size: var(--font-size-xs); white-space: nowrap; font-variant-numeric: tabular-nums; }
.library-tile-source { margin: 0; color: var(--color-text-muted); font-size: var(--font-size-xs); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* Skeleton cards while the first answer is on its way. */
.library-tile.is-skeleton { border: 1px solid var(--color-divider); border-radius: var(--radius-md); overflow: hidden; background: var(--color-surface); }
.library-preview-skeleton { animation: productionstudio-pulse var(--motion-duration-loop) ease-in-out infinite; }
.library-tile.is-skeleton .skeleton-line:first-child { width: 40%; }
@media (prefers-reduced-motion: reduce) {
  .library-preview-skeleton { animation: none; }
}

/* List view: one row per item with a small preview. */
.library-results[data-view="list"] { grid-template-columns: minmax(0, 1fr); gap: var(--space-2); }
.library-results[data-view="list"] .library-tile-card { grid-template-columns: 168px minmax(0, 1fr); grid-template-rows: none; }
.library-results[data-view="list"] .library-preview { aspect-ratio: auto; min-height: 96px; }
.library-status-inline { display: none; }
.library-results[data-view="list"] .library-preview > .library-status { display: none; }
.library-results[data-view="list"] .library-status-inline { display: inline-block; max-width: 100%; position: static; box-shadow: none; white-space: normal; }
.library-results[data-view="list"] .library-tile-body { padding: var(--space-2-5) var(--space-3-5); }
.library-results[data-view="list"] .library-tile-topic { -webkit-line-clamp: 1; }

/* Empty catalogue and no matches. */
.library-empty[hidden] { display: none; }
.library-empty-state { justify-items: center; padding: var(--space-10) var(--space-6); text-align: center; }
.library-empty-state .library-glyph { width: 40px; height: 40px; margin-bottom: var(--space-1); color: var(--color-text-muted); }
.library-empty-state .empty-state-title { font-size: var(--font-size-lg); }
.library-empty-state .empty-state-hint { max-width: 460px; line-height: var(--line-height-relaxed); }
.library-empty-state button { margin-top: var(--space-2); }

/* ---- The open item ---------------------------------------------------------------------- */
.library-detail {
  display: block;
  min-width: 0;
  padding: var(--space-4);
  border: 1px solid var(--color-divider);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  box-shadow: var(--shadow-md);
  overflow-wrap: anywhere;
}
.library-detail[hidden] { display: none; }
/* A block, not a grid: a grid row would let the height-capped panel squeeze the 16:9 preview. */
.library-detail > * + * { margin-top: var(--space-3); }
.library-detail:focus { outline: none; }
.library-detail-head { display: flex; justify-content: space-between; align-items: center; }
.library-detail-back::before { content: "\2190"; margin-right: var(--space-1-5); }
.library-detail .library-preview { border-radius: var(--radius-md); }
.library-detail-kicker { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2); }
.library-detail-title { margin: 0; font-size: var(--font-size-h3); }
/* The title takes focus when the item opens (a heading, not a control: no ring). */
.library-detail-title:focus { outline: none; }
.library-detail > .library-detail-topic { margin-top: var(--space-1); font-size: var(--font-size-md); }
.library-detail > .library-detail-objective { margin-top: var(--space-1); margin-bottom: 0; line-height: var(--line-height-relaxed); }
.library-detail-topic { margin-bottom: 0; }
.library-facts { padding: var(--space-3); border-radius: var(--radius-md); background: var(--color-surface-2); font-size: var(--font-size-sm); }
.library-actions { gap: var(--space-2); }
.library-actions-hint { margin: 0; font-size: var(--font-size-xs); }
.library-section { display: grid; gap: var(--space-2); padding-top: var(--space-3); border-top: 1px solid var(--color-divider); }
.library-section > h4 { margin: 0; }

/* Lineage: the admitted source, the units cut from it, this unit's approved renditions. */
.library-lineage, .library-lineage-units, .library-lineage-renditions { margin: 0; padding: 0; list-style: none; }
.library-node { position: relative; display: grid; gap: var(--space-0-5); min-width: 0; font-size: var(--font-size-sm); }
.library-node.is-source { padding: var(--space-2-5) var(--space-3); border: 1px solid var(--color-divider-strong); border-radius: var(--radius-md); background: var(--color-surface-2); }
.library-node-kicker { color: var(--color-text-muted); font-size: var(--font-size-xs); font-weight: var(--font-weight-semibold); }
.library-node-title { font-weight: var(--font-weight-semibold); }
.library-node-meta { color: var(--color-text-muted); font-size: var(--font-size-xs); }
.library-node-meta:empty { display: none; }
.library-lineage-units { display: grid; gap: var(--space-2); margin-top: var(--space-2-5); padding-left: var(--space-5); border-left: 2px solid var(--color-divider-strong); margin-left: var(--space-1); }
.library-node.is-unit { padding: var(--space-2) var(--space-2-5); border: 1px solid var(--color-divider); border-radius: var(--radius-sm); background: var(--color-surface); }
.library-node.is-unit::before { content: ""; position: absolute; top: 50%; left: calc(-1 * var(--space-5)); width: calc(var(--space-5) - 2px); border-top: 2px solid var(--color-divider-strong); }
.library-node.is-unit.is-current { border-color: var(--color-accent); background: var(--color-selected); }
.library-node.is-current > .library-node-kicker { color: var(--color-accent); }
.library-node.is-current::before { top: var(--space-4); border-color: var(--color-accent); }
button.library-node-open { justify-content: flex-start; min-height: 0; padding: 0; color: var(--color-text); font-size: var(--font-size-sm); text-align: left; text-decoration-line: underline; text-decoration-color: var(--color-divider-strong); text-underline-offset: 3px; }
button.library-node-open:hover:not(:disabled) { background: transparent; color: var(--color-accent); text-decoration-color: currentcolor; }
.library-lineage-renditions { display: grid; gap: var(--space-1); margin-top: var(--space-2); padding-left: var(--space-3); border-left: 2px solid var(--color-accent-subtle-hover); }
.library-node.is-rendition { grid-template-columns: minmax(0, 1fr) auto; align-items: baseline; gap: var(--space-2); padding: var(--space-1) 0; }

.library-versions { display: grid; gap: var(--space-1-5); margin: 0; padding: 0; list-style: none; }
.library-versions li { display: flex; flex-wrap: wrap; align-items: baseline; justify-content: space-between; gap: var(--space-1) var(--space-3); padding: var(--space-1-5) 0; border-bottom: 1px solid var(--color-divider); font-size: var(--font-size-sm); }
.library-versions li:last-child { border-bottom: 0; }

/* Below lg the open item takes the catalogue's place (with a way back). */
@media (width < 1280px) {
  .library-layout[data-detail="open"] .library-results,
  .library-layout[data-detail="open"] .library-empty { display: none; }
}
/* From lg the item sits beside the catalogue, which keeps scrolling on its own. */
@media (width >= 1280px) {
  .library-layout[data-detail="open"] { grid-template-columns: minmax(0, 1fr) minmax(360px, 420px); }
  .library-layout[data-detail="open"] .library-detail { position: sticky; top: calc(var(--size-shell-header) + var(--space-4)); max-height: calc(100vh - var(--size-shell-header) - var(--space-8)); overflow-y: auto; }
  .library-detail-back::before { content: none; }
}
@media (width < 1024px) {
  .library-filters { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .library-filter-search { grid-column: 1 / -1; }
}
@media (width < 600px) {
  .library-filters { gap: var(--space-2-5); padding: var(--space-3); }
  .library-results[data-view="list"] .library-tile-card { grid-template-columns: 112px minmax(0, 1fr); }
  .library-detail { padding: var(--space-3); }
  .library-empty-state { padding: var(--space-8) var(--space-4); }
}
@media (prefers-reduced-motion: reduce) {
  .library-tile-card { transition: none; }
}