.lecture-map-shell {
  --lecture-map-panel-height: clamp(560px, 68vh, 760px);
  display: grid;
  gap: 14px;
  margin-top: 14px;
}

.lecture-map-head {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 14px;
  align-items: start;
}

.lecture-map-head div {
  display: grid;
  gap: 4px;
}

.lecture-map-head span {
  color: var(--muted);
  font-weight: 800;
}

.lecture-map-toolbar {
  display: grid;
  grid-template-columns: minmax(220px, 1fr) auto;
  gap: 10px;
  align-items: center;
}

.lecture-map-path {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.lecture-map-path button {
  min-height: 34px;
  padding: 0 10px;
  border: 1px solid rgba(190,148,255,.22);
  border-radius: 8px;
  color: var(--muted);
  background: rgba(255,255,255,.045);
  font-weight: 800;
  cursor: pointer;
}

.lecture-map-path button:last-child {
  color: var(--text);
  border-color: rgba(45,212,191,.5);
  background: rgba(45,212,191,.1);
}

.lecture-map-workspace {
  display: grid;
  grid-template-columns: minmax(260px, .8fr) minmax(360px, 1.15fr) minmax(280px, .85fr);
  gap: 14px;
  align-items: stretch;
  min-width: 0;
}

.lecture-map-sidebar,
.lecture-map-main,
.lecture-node-detail {
  min-width: 0;
  min-height: var(--lecture-map-panel-height);
  max-height: var(--lecture-map-panel-height);
  border: 1px solid rgba(190,148,255,.22);
  border-radius: 8px;
  background:
    radial-gradient(circle at 50% 0%, rgba(124,58,237,.18), transparent 220px),
    linear-gradient(180deg, rgba(20, 9, 42, .76), rgba(8, 3, 18, .76));
  box-shadow: inset 0 0 0 1px rgba(255,255,255,.02);
}

.lecture-map-sidebar {
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  overflow: hidden;
}

.lecture-tree-head {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 12px;
  border-bottom: 1px solid rgba(190,148,255,.16);
}

.lecture-tree-head span {
  color: var(--muted);
  font-weight: 800;
}

.lecture-node-list {
  display: block;
  min-height: 0;
  max-height: none;
  overflow: auto;
  padding: 8px;
  border: 0;
  border-radius: 0;
  background: transparent;
  scrollbar-color: rgba(190,148,255,.42) transparent;
  scroll-behavior: auto;
}

.lecture-tree-node {
  display: grid;
  gap: 4px;
}

.lecture-tree-children {
  display: grid;
  gap: 4px;
  margin-left: 14px;
  padding-left: 10px;
  border-left: 1px solid rgba(190,148,255,.14);
}

.lecture-tree-node button {
  width: 100%;
  min-width: 0;
  display: grid;
  grid-template-columns: 10px minmax(0, 1fr) auto;
  gap: 8px;
  align-items: center;
  min-height: 42px;
  padding: 8px;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--text);
  background: transparent;
  cursor: pointer;
  text-align: left;
  transition: border-color .16s ease, background .16s ease, transform .16s ease, box-shadow .16s ease;
}

.lecture-tree-node button:hover,
.lecture-tree-node button.active {
  border-color: rgba(45,212,191,.5);
  background: rgba(45,212,191,.1);
}

.lecture-tree-node button:hover {
  transform: translateX(2px);
  box-shadow: 0 8px 20px rgba(45,212,191,.06);
}

.lecture-tree-dot {
  width: 8px;
  height: 8px;
  border-radius: 99px;
  background: rgba(192,132,252,.9);
  box-shadow: 0 0 12px rgba(192,132,252,.35);
}

.lecture-tree-node.depth-1 .lecture-tree-dot {
  background: rgba(45,212,191,.95);
}

.lecture-tree-node.depth-2 .lecture-tree-dot,
.lecture-tree-node.depth-3 .lecture-tree-dot {
  background: rgba(253,230,138,.9);
}

.lecture-tree-node b,
.lecture-tree-node small {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.lecture-tree-node small {
  color: var(--muted);
  font-weight: 800;
}

.lecture-map-main {
  display: grid;
  overflow: hidden;
}

.lecture-graph {
  min-height: 100%;
  height: 100%;
  overflow: hidden;
  border: 0;
  border-radius: 8px;
  background:
    linear-gradient(rgba(255,255,255,.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,.035) 1px, transparent 1px),
    rgba(10, 4, 26, .36);
  background-size: 28px 28px;
  box-shadow: inset 0 0 80px rgba(124,58,237,.12);
}

.lecture-graph svg {
  display: block;
  width: 100%;
  height: 100%;
  min-height: var(--lecture-map-panel-height);
}

.lecture-graph-links path {
  fill: none;
  stroke: rgba(190,148,255,.24);
  stroke-width: 1.2;
}

.lecture-graph-node {
  cursor: pointer;
  transition: opacity .16s ease;
}

.lecture-graph-node circle {
  fill: rgba(45,212,191,.88);
  stroke: rgba(255,255,255,.64);
  stroke-width: 1.5;
  filter: drop-shadow(0 0 8px rgba(45,212,191,.35));
}

.lecture-graph-node.active circle {
  fill: rgba(232,121,249,.96);
  stroke: rgba(255,255,255,.92);
  filter: drop-shadow(0 0 16px rgba(232,121,249,.7));
}

.lecture-graph-node text {
  fill: rgba(244,238,255,.9);
  font-size: 12px;
  font-weight: 800;
  paint-order: stroke;
  stroke: rgba(10,4,26,.8);
  stroke-width: 3px;
}

.lecture-graph-node:hover circle {
  stroke: #fff;
  filter: drop-shadow(0 0 14px rgba(45,212,191,.72));
}

.lecture-node-detail {
  overflow: auto;
  padding: 16px;
  scrollbar-color: rgba(190,148,255,.42) transparent;
}

.lecture-node-detail h4 {
  margin: 0 0 8px;
  font-size: 20px;
}

.lecture-node-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 12px;
}

.lecture-node-stats span,
.lecture-node-pages {
  color: var(--pink);
  font-weight: 900;
}

.lecture-node-detail p {
  margin: 0 0 14px;
  color: var(--muted);
}

.lecture-node-detail section {
  margin-top: 14px;
}

.lecture-node-detail ul {
  margin: 8px 0 0;
  padding-left: 18px;
}

.lecture-node-detail li {
  margin: 6px 0;
}

.lecture-node-pages {
  margin-top: 14px;
}

@media (max-width: 1100px) {
  .lecture-map-shell {
    --lecture-map-panel-height: auto;
  }

  .lecture-map-workspace {
    grid-template-columns: 1fr;
  }

  .lecture-map-sidebar,
  .lecture-node-detail {
    min-height: 0;
    max-height: 420px;
  }

  .lecture-map-main {
    min-height: 420px;
    max-height: 420px;
  }

  .lecture-graph {
    min-height: 420px;
  }

  .lecture-graph svg {
    min-height: 420px;
  }
}

@media (max-width: 640px) {
  .lecture-map-head,
  .lecture-map-toolbar {
    grid-template-columns: 1fr;
  }

  .lecture-map-path {
    flex-wrap: nowrap;
    overflow-x: auto;
    padding-bottom: 2px;
  }

  .lecture-map-path button {
    flex: 0 0 auto;
    max-width: 78vw;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .lecture-graph,
  .lecture-graph svg {
    min-height: 340px;
  }

  .lecture-map-main {
    min-height: 340px;
    max-height: 340px;
  }
}