/* Backing library: the same light Memphis card system used by the learning library. */
[data-screen-section][hidden] {
  display: none !important;
}

.backing-library {
  padding: clamp(22px, 3vw, 42px);
  border: 4px solid var(--mem-ink);
  border-radius: var(--mem-radius);
  background: var(--mem-paper);
  box-shadow: var(--mem-shadow);
}

.backing-library-heading,
.backing-results > header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 28px;
}

.backing-library-heading {
  padding-bottom: clamp(20px, 2.5vw, 34px);
  border-bottom: 3px solid var(--mem-ink);
}

.backing-library-heading h1 {
  margin: 4px 0 0;
  color: var(--mem-ink);
  font: 900 clamp(32px, 4.6vw, 68px)/.98 var(--mem-display);
  letter-spacing: -.045em;
}

.backing-library-heading > p {
  max-width: 590px;
  margin: 0;
  color: var(--mem-ink);
  font: 700 clamp(15px, 1.25vw, 19px)/1.55 var(--mem-body);
}

.backing-taxonomy {
  margin-top: clamp(20px, 2.5vw, 32px);
}

.backing-axis-tabs {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: clamp(10px, 1.2vw, 16px);
  margin: 0 0 clamp(14px, 1.7vw, 22px);
  padding: 6px 6px 8px;
}

.backing-axis-tabs button,
.backing-category-card,
.backing-result-card {
  border: 3px solid var(--mem-ink);
  color: var(--mem-ink);
  box-shadow: 4px 5px 0 rgba(24, 49, 83, .16), 0 10px 22px rgba(24, 49, 83, .08);
  transition: transform 160ms ease, box-shadow 160ms ease, background-color 160ms ease;
}

.backing-axis-tabs button {
  position: relative;
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas: "index title" "index note";
  align-items: center;
  gap: 2px 12px;
  min-height: 96px;
  padding: 16px 18px;
  border-radius: 15px;
  text-align: left;
}

.backing-axis-tabs button:nth-child(1) { background: var(--mem-yellow); }
.backing-axis-tabs button:nth-child(2) { background: var(--mem-sky); }
.backing-axis-tabs button:nth-child(3) { background: var(--mem-mint); }
.backing-axis-tabs button:nth-child(4) { background: var(--mem-coral); }

.backing-axis-tabs button span {
  grid-area: index;
  font: 900 16px/1 var(--mem-data);
}

.backing-axis-tabs button strong {
  grid-area: title;
  font: 900 clamp(22px, 2.05vw, 31px)/1 var(--mem-display);
  letter-spacing: -.025em;
}

.backing-axis-tabs button small {
  grid-area: note;
  font: 800 12px/1.2 var(--mem-body);
}

.backing-axis-tabs button.active {
  z-index: 2;
  border-color: var(--mem-ink);
  color: var(--mem-ink);
  background: var(--mem-paper);
  box-shadow: 0 0 0 5px var(--mem-coral), 6px 7px 0 rgba(24, 49, 83, .2);
  transform: translateY(-3px);
}

.backing-axis-tabs button.active::after {
  content: "";
  position: absolute;
  right: 14px;
  bottom: 12px;
  width: 11px;
  height: 11px;
  border: 2px solid var(--mem-ink);
  border-radius: 50%;
  background: var(--mem-coral);
}

.backing-category-browser {
  overflow: hidden;
  border: 3px solid var(--mem-ink);
  border-radius: 18px;
  background: var(--mem-coral);
  box-shadow: 7px 8px 0 rgba(24, 49, 83, .16), 0 14px 30px rgba(24, 49, 83, .08);
}

.backing-category-window-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  min-height: 47px;
  padding: 10px 16px;
  border-bottom: 3px solid var(--mem-ink);
  background: var(--mem-paper);
}

.backing-category-window-bar > span {
  width: 12px;
  height: 12px;
  border: 2px solid var(--mem-ink);
  border-radius: 50%;
  background: var(--mem-coral);
}

.backing-category-window-bar > span:nth-child(2) { background: var(--mem-yellow); }
.backing-category-window-bar > span:nth-child(3) { background: var(--mem-mint); }

.backing-category-window-bar strong {
  margin-left: 6px;
  font: 900 clamp(13px, 1.1vw, 16px)/1.2 var(--mem-body);
  letter-spacing: .02em;
}

.backing-category-rail {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(210px, 1fr);
  gap: 14px;
  padding: 22px 20px 25px;
  overflow-x: auto;
  scroll-padding-inline: 20px;
  scroll-snap-type: x proximity;
  scrollbar-color: var(--mem-ink) transparent;
}

.backing-category-card {
  --category-fill: var(--mem-yellow);
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: space-between;
  min-height: 158px;
  padding: 16px;
  border-radius: 14px;
  text-align: left;
  scroll-snap-align: start;
  background: var(--category-fill);
}

.backing-category-card:nth-child(4n + 2) { --category-fill: var(--mem-sky); }
.backing-category-card:nth-child(4n + 3) { --category-fill: var(--mem-mint); }
.backing-category-card:nth-child(4n + 4) { --category-fill: #ffc7c1; }

.backing-category-card > span,
.backing-category-card > small {
  font: 900 11px/1.15 var(--mem-data);
}

.backing-category-card h3 {
  max-width: 16ch;
  margin: auto 0 7px;
  font: 900 clamp(17px, 1.45vw, 22px)/1.08 var(--mem-display);
}

.backing-category-card p {
  min-height: 2.5em;
  margin: 0 0 15px;
  font: 750 12px/1.25 var(--mem-body);
}

.backing-category-card.active {
  background: var(--mem-paper);
  box-shadow: 0 0 0 5px var(--mem-yellow), 6px 7px 0 rgba(24, 49, 83, .23);
  transform: translateY(-3px);
}

.backing-results {
  margin-top: 32px;
  padding-top: 28px;
  border-top: 3px solid var(--mem-ink);
}

.backing-results > header {
  align-items: center;
  margin-bottom: 18px;
}

.backing-results h2 {
  margin: 2px 0 0;
  color: var(--mem-ink);
  font: 900 clamp(25px, 2.8vw, 42px)/1 var(--mem-display);
}

#backingResultsCount {
  padding: 9px 13px;
  border: 2px solid var(--mem-ink);
  border-radius: 9px;
  background: var(--mem-mint);
  font: 900 14px/1 var(--mem-data);
}

.backing-result-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.backing-result-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 238px;
  padding: 20px;
  border-radius: 14px;
  background: var(--mem-yellow);
}

.backing-result-card:nth-child(4n + 2) { background: var(--mem-mint); }
.backing-result-card:nth-child(4n + 3) { background: var(--mem-sky); }
.backing-result-card:nth-child(4n + 4) { background: #ffc7c1; }

.backing-result-badge {
  display: inline-block;
  margin-bottom: 20px;
  color: #8e302c;
  font: 900 12px/1 var(--mem-data);
  letter-spacing: .06em;
}

.backing-result-card h3 {
  margin: 0 0 9px;
  overflow-wrap: anywhere;
  font: 900 clamp(22px, 2.1vw, 34px)/1.02 var(--mem-display);
}

.backing-result-card p {
  margin: 0;
  font: 650 14px/1.45 var(--mem-body);
}

.backing-result-card footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  max-width: none;
  margin: 24px 0 0;
  padding: 14px 0 0;
  border: 0;
  border-top: 2px solid var(--mem-ink);
  border-radius: 0;
  color: var(--mem-ink);
  background: transparent;
  box-shadow: none;
}

.backing-result-card footer > span {
  font: 850 12px/1.3 var(--mem-data);
}

.backing-result-card footer button {
  min-height: 44px;
  padding: 10px 13px;
  border: 2px solid var(--mem-ink);
  border-radius: 9px;
  color: var(--mem-ink);
  background: var(--mem-paper);
  font: 900 14px/1 var(--mem-body);
  transition: transform 150ms ease, background-color 150ms ease;
}

.backing-library-empty {
  grid-column: 1 / -1;
  padding: 34px;
  border: 3px dashed var(--mem-ink);
  border-radius: 14px;
  background: var(--mem-mint);
}

.backing-library-empty strong {
  font: 900 clamp(20px, 2vw, 28px)/1.1 var(--mem-display);
}

.backing-library-empty p { margin-bottom: 0; }

.backing-axis-tabs button:focus-visible,
.backing-category-card:focus-visible,
.backing-result-card footer button:focus-visible {
  outline: 4px solid #2f6bff;
  outline-offset: 3px;
}

@media (hover: hover) and (pointer: fine) {
  .backing-axis-tabs button:not(.active):hover,
  .backing-category-card:not(.active):hover,
  .backing-result-card:hover {
    box-shadow: 7px 8px 0 rgba(24, 49, 83, .2), 0 16px 28px rgba(24, 49, 83, .1);
    transform: translateY(-5px) rotate(-.35deg);
  }

  .backing-axis-tabs button:nth-child(even):not(.active):hover,
  .backing-category-card:nth-child(even):not(.active):hover,
  .backing-result-card:nth-child(even):hover {
    transform: translateY(-5px) rotate(.35deg);
  }

  .backing-result-card footer button:hover {
    background: var(--mem-coral);
    transform: translateY(-2px);
  }
}

body[data-screen="backings"] .skip-link,
body[data-screen="library"] .skip-link,
body[data-screen="knowledge"] .skip-link { display: none; }

@media (max-width: 900px) {
  .backing-library-heading {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
  }

  .backing-axis-tabs {
    grid-template-columns: none;
    grid-auto-flow: column;
    grid-auto-columns: clamp(148px, 27vw, 198px);
    overflow-x: auto;
    scroll-padding-inline: 6px;
    scrollbar-width: thin;
  }

  .backing-axis-tabs button {
    min-height: 80px;
    padding: 12px 14px;
  }

  .backing-category-rail { grid-auto-columns: clamp(170px, 34vw, 224px); }
  .backing-category-card { min-height: 136px; padding: 13px; }
  .backing-result-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 620px) {
  .backing-library {
    padding: 17px;
    border-width: 3px;
  }

  .backing-library-heading h1 { font-size: clamp(32px, 11vw, 48px); }
  .backing-taxonomy { margin-top: 16px; }
  .backing-axis-tabs { gap: 8px; margin-bottom: 13px; padding: 5px 5px 7px; }
  .backing-axis-tabs button { min-height: 68px; padding: 9px 10px; border-width: 2px; border-radius: 10px; }
  .backing-axis-tabs button.active { box-shadow: 0 0 0 3px var(--mem-coral), 4px 5px 0 rgba(24, 49, 83, .18); }
  .backing-axis-tabs button.active::after { right: 9px; bottom: 8px; width: 9px; height: 9px; }
  .backing-axis-tabs button strong { font-size: 20px; }
  .backing-axis-tabs button span { font-size: 12px; }
  .backing-axis-tabs button small { font-size: 9px; }
  .backing-category-browser { border-width: 2px; border-radius: 13px; }
  .backing-category-window-bar { min-height: 42px; padding: 8px 11px; border-bottom-width: 2px; }
  .backing-category-window-bar > span { width: 10px; height: 10px; border-width: 1.5px; }
  .backing-category-window-bar strong { overflow: hidden; font-size: 12px; text-overflow: ellipsis; white-space: nowrap; }
  .backing-category-rail { grid-auto-columns: clamp(148px, 50vw, 184px); gap: 9px; padding: 15px 12px 18px; scroll-padding-inline: 12px; }
  .backing-category-card { min-height: 116px; padding: 11px; border-width: 2px; border-radius: 10px; box-shadow: 3px 4px 0 rgba(24, 49, 83, .17); }
  .backing-category-card > span,
  .backing-category-card > small { font-size: 9px; }
  .backing-category-card h3 { margin-bottom: 5px; font-size: clamp(15px, 4.4vw, 18px); }
  .backing-category-card p { min-height: 2.35em; margin-bottom: 9px; font-size: 10px; }
  .backing-category-card.active { box-shadow: 0 0 0 3px var(--mem-yellow), 4px 5px 0 rgba(24, 49, 83, .2); }
  .backing-results { margin-top: 24px; padding-top: 22px; }
  .backing-results > header { align-items: flex-start; flex-direction: column; gap: 10px; }
  .backing-result-grid { grid-template-columns: 1fr; }
  .backing-result-card { min-height: 205px; }
}

@media (prefers-reduced-motion: reduce) {
  .backing-axis-tabs button,
  .backing-category-card,
  .backing-result-card,
  .backing-result-card footer button {
    transition: none;
    transform: none !important;
  }
}