.ontology-hero {
  display: grid;
  gap: 2rem;
  align-items: end;
}

.ontology-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.75rem;
  margin: 0;
}

.ontology-stats div {
  min-width: 0;
  padding: 1rem;
  border: 1px solid var(--plx-border);
  border-radius: var(--plx-radius-sm);
  background: var(--plx-surface-strong);
}

.ontology-stats dt,
.ontology-selection__meta dt {
  color: var(--plx-muted);
  font-size: 0.72rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.ontology-stats dd {
  margin: 0.2rem 0 0;
  color: var(--plx-primary-hover);
  font-size: 1.8rem;
  font-weight: 850;
  line-height: 1;
}

.ontology-browser {
  margin-top: clamp(2.75rem, 6vw, 5rem);
  scroll-margin-top: 1rem;
}

.ontology-browser__heading,
.ontology-panel-heading {
  display: flex;
  gap: 1rem;
  align-items: center;
  justify-content: space-between;
}

.ontology-browser__heading h2,
.ontology-panel-heading h3,
.ontology-about h2 {
  margin: 0;
}

.ontology-browser__heading h2 {
  font-size: clamp(1.65rem, 4vw, 2.35rem);
}

.ontology-browser__heading .plx-help {
  max-width: 48rem;
  margin-top: 0.45rem;
}

.ontology-toolbar {
  display: grid;
  grid-template-columns: minmax(14rem, 1fr) auto;
  gap: 1rem 1.25rem;
  align-items: end;
  margin-top: 1.25rem;
  padding: 1.25rem;
}

.ontology-filters {
  display: grid;
  grid-template-columns: minmax(12rem, 1.5fr) minmax(11rem, 0.75fr);
  gap: 0.75rem;
  min-width: 0;
}

.ontology-search {
  display: grid;
  gap: 0.4rem;
  min-width: 0;
}

.ontology-search label {
  color: #334155;
  font-size: 0.88rem;
  font-weight: 750;
}

.ontology-search input {
  width: 100%;
}

.ontology-actions,
.ontology-related {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.ontology-status {
  grid-column: 1 / -1;
  margin: 0;
  color: var(--plx-muted);
  font-size: 0.86rem;
}

.ontology-workbench {
  display: grid;
  gap: 1.25rem;
  min-width: 0;
  margin-top: 1.25rem;
}

.ontology-tree-panel,
.ontology-selection {
  min-width: 0;
  overflow: hidden;
}

.ontology-panel-heading {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--plx-border);
  background: linear-gradient(135deg, #eef2ff, #f0fdfa);
}

.ontology-tree-scroll {
  max-height: min(68rem, 72vh);
  padding: 1rem 1.25rem 1.5rem;
  overflow: auto;
  scrollbar-gutter: stable;
}

.ontology-tree,
.ontology-tree ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.ontology-tree ul {
  margin-left: 0.65rem;
  padding-left: 1.05rem;
  border-left: 1px solid #cbd5e1;
}

.ontology-tree li {
  min-width: 0;
  margin: 0.24rem 0;
}

.ontology-tree details > summary,
.ontology-leaf {
  width: 100%;
  min-height: 2.35rem;
  color: #334155;
  text-align: left;
  overflow-wrap: anywhere;
}

.ontology-tree details > summary {
  display: flex;
  gap: 0.55rem;
  align-items: flex-start;
  padding: 0.38rem 0.5rem;
  border-radius: var(--plx-radius-sm);
  cursor: pointer;
  list-style: none;
  font-weight: 750;
}

.ontology-tree details > summary::-webkit-details-marker {
  display: none;
}

.ontology-tree details > summary::before {
  content: "";
  flex: none;
  width: 0.48rem;
  height: 0.48rem;
  border-right: 2px solid var(--plx-primary);
  border-bottom: 2px solid var(--plx-primary);
  transform: rotate(-45deg);
  transition: transform 120ms ease;
}

.ontology-tree details[open] > summary::before {
  transform: rotate(45deg) translate(-0.08rem, -0.08rem);
}

.ontology-tree details > summary:hover,
.ontology-leaf:hover,
.ontology-leaf[aria-current="true"] {
  color: var(--plx-primary-hover);
  background: var(--plx-primary-soft);
}

.ontology-node-count {
  flex: none;
  margin-left: auto;
  padding: 0.12rem 0.42rem;
  border-radius: 999px;
  color: var(--plx-accent-hover);
  background: var(--plx-accent-soft);
  font-size: 0.7rem;
  font-weight: 800;
}

.ontology-leaf {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  padding: 0.4rem 0.55rem 0.4rem 1.5rem;
  border: 0;
  border-radius: var(--plx-radius-sm);
  background: transparent;
  cursor: pointer;
}

.ontology-leaf::before {
  content: "";
  flex: none;
  width: 0.45rem;
  height: 0.45rem;
  border-radius: 999px;
  background: var(--plx-accent);
  margin-top: 0.55rem;
}

.ontology-leaf__content {
  display: grid;
  gap: 0.08rem;
  min-width: 0;
}

.ontology-leaf__name {
  color: inherit;
  font-weight: 750;
}

.ontology-leaf__examples {
  color: var(--plx-muted);
  overflow-wrap: anywhere;
  font-size: 0.78rem;
  font-weight: 500;
  line-height: 1.45;
}

.ontology-terminal-branch {
  margin: 0.25rem 0 0.35rem;
}

.ontology-selection__body {
  padding: 1.25rem;
}

.ontology-selection__empty {
  margin: 0;
  color: var(--plx-muted);
}

.ontology-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.ontology-breadcrumb li {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  min-width: 0;
  color: var(--plx-primary-hover);
  overflow-wrap: anywhere;
  font-size: 0.88rem;
  font-weight: 750;
}

.ontology-breadcrumb li:not(:last-child)::after {
  content: "›";
  color: #94a3b8;
}

.ontology-selection__meta {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
  margin: 1.25rem 0;
}

.ontology-selection__meta div {
  min-width: 0;
  padding: 0.8rem;
  border: 1px solid var(--plx-border);
  border-radius: var(--plx-radius-sm);
  background: #f8fafc;
}

.ontology-selection__meta dd {
  margin: 0.15rem 0 0;
  overflow-wrap: anywhere;
  font-weight: 750;
}

.ontology-examples {
  margin: 0 0 1.25rem;
}

.ontology-examples h4 {
  margin: 0 0 0.55rem;
  font-size: 0.92rem;
}

.ontology-examples ul {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0;
  padding: 0;
  list-style: none;
}

.ontology-examples li {
  padding: 0.28rem 0.55rem;
  border: 1px solid #99f6e4;
  border-radius: var(--plx-radius-sm);
  color: var(--plx-accent-hover);
  background: #f0fdfa;
  overflow-wrap: anywhere;
  font-size: 0.8rem;
  font-weight: 700;
}

.ontology-about {
  margin-top: clamp(2.75rem, 6vw, 5rem);
  scroll-margin-top: 1rem;
}

.ontology-about p {
  max-width: 72ch;
  margin: 0.9rem 0 0;
  color: #475569;
}

.ontology-help-grid {
  display: grid;
  gap: 0.75rem;
  margin-top: 1.1rem;
}

.ontology-help-grid details {
  border: 1px solid var(--plx-border);
  border-radius: var(--plx-radius-sm);
  background: var(--plx-surface-strong);
}

.ontology-help-grid summary {
  padding: 0.8rem 1rem;
  color: var(--plx-primary-hover);
  cursor: pointer;
  font-weight: 800;
}

.ontology-help-grid details[open] summary {
  border-bottom: 1px solid var(--plx-border);
  background: var(--plx-primary-soft);
}

.ontology-help-grid details p {
  padding-inline: 1rem;
}

.ontology-help-grid details p:last-child {
  margin-bottom: 1rem;
}

.ontology-related {
  margin-top: 1.25rem;
}

.ontology-related a {
  padding: 0.45rem 0.7rem;
  border: 1px solid var(--plx-border);
  border-radius: var(--plx-radius-sm);
  background: var(--plx-surface-strong);
  font-size: 0.86rem;
  font-weight: 750;
  text-decoration: none;
}

.ontology-error {
  margin: 0;
  padding: 1rem;
  border: 1px solid #fecaca;
  border-radius: var(--plx-radius-sm);
  color: #991b1b;
  background: #fef2f2;
}

@media (min-width: 64rem) {
  .ontology-hero {
    grid-template-columns: minmax(0, 1fr) minmax(22rem, 0.55fr);
  }

  .ontology-workbench {
    grid-template-columns: minmax(0, 1.7fr) minmax(18rem, 0.75fr);
    align-items: start;
  }

  .ontology-selection {
    position: sticky;
    top: 1rem;
  }
}

@media (max-width: 48rem) {
  .ontology-browser__heading,
  .ontology-panel-heading {
    align-items: flex-start;
    flex-direction: column;
  }

  .ontology-browser__heading > a {
    width: 100%;
  }

  .ontology-toolbar {
    grid-template-columns: minmax(0, 1fr);
  }

  .ontology-filters {
    grid-template-columns: minmax(0, 1fr);
  }

  .ontology-status {
    grid-column: 1;
  }

  .ontology-actions > button {
    flex: 1 1 9rem;
  }
}

@media (max-width: 30rem) {
  .ontology-stats,
  .ontology-selection__meta {
    grid-template-columns: minmax(0, 1fr);
  }

  .ontology-tree-scroll {
    padding-inline: 0.75rem;
  }

  .ontology-tree ul {
    margin-left: 0.2rem;
    padding-left: 0.65rem;
  }
}