.lesion-learning-sequence {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: .8rem;
  margin: 1rem 0 1.25rem;
}

.lesion-learning-sequence article {
  position: relative;
  min-width: 0;
  padding: 1rem;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-surface-soft);
}

.lesion-learning-sequence article::after {
  position: absolute;
  top: 50%;
  right: -.72rem;
  z-index: 1;
  color: var(--color-primary);
  content: "→";
  font-weight: 800;
  transform: translateY(-50%);
}

.lesion-learning-sequence article:last-child::after { content: none; }
.lesion-learning-sequence h3 { margin: 0 0 .35rem; font-size: 1rem; }
.lesion-learning-sequence p { margin: 0; color: var(--color-ink-soft); }

.unified-lesion-card {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
  box-shadow: var(--shadow-soft);
}

.unified-lesion-card > summary {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: flex-start;
  padding: 1.05rem 1.15rem;
  cursor: pointer;
  list-style: none;
}

.unified-lesion-card > summary::-webkit-details-marker { display: none; }
.unified-lesion-card > summary::after { content: "+"; color: var(--color-primary); font-size: 1.35rem; font-weight: 800; }
.unified-lesion-card[open] > summary::after { content: "−"; }
.unified-lesion-card__title { display: block; font-size: 1.08rem; font-weight: 800; }
.unified-lesion-card__english { display: block; margin-top: .18rem; color: var(--color-ink-soft); font-size: .88rem; }
.unified-lesion-card__body { display: grid; gap: 1rem; padding: 0 1.15rem 1.15rem; border-top: 1px solid var(--color-line); }
.unified-lesion-card__badges { margin-top: 1rem; }

.normal-background-lesion {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: .75rem;
}

.normal-background-lesion article {
  min-width: 0;
  padding: .9rem;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background: var(--color-surface-soft);
}

.normal-background-lesion article:nth-child(1) { border-top: 4px solid #4c8577; }
.normal-background-lesion article:nth-child(2) { border-top: 4px solid #b3915d; }
.normal-background-lesion article:nth-child(3) { border-top: 4px solid #b76554; }
.normal-background-lesion h3 { margin: 0 0 .35rem; font-size: 1rem; }
.normal-background-lesion p { margin: .35rem 0; }
.normal-background-lesion ul { margin-bottom: 0; }

.unified-lesion-section { min-width: 0; }
.unified-lesion-section h3 { margin: 0 0 .45rem; font-size: 1rem; }
.unified-lesion-section ul { margin-bottom: 0; }
.unified-lesion-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: .75rem; }
.unified-lesion-grid > section { padding: .9rem; border: 1px solid var(--color-line); border-radius: var(--radius-md); }

.textbook-crosscheck {
  padding: .9rem;
  border: 1px dashed var(--color-line-strong);
  border-radius: var(--radius-md);
  background: #fbfcfc;
}

.textbook-crosscheck summary { cursor: pointer; font-weight: 800; }
.textbook-source-list { display: grid; gap: .55rem; margin: .75rem 0 0; padding: 0; list-style: none; }
.textbook-source-list li { padding: .6rem .7rem; border-left: 3px solid var(--color-primary); background: var(--color-surface-soft); }
.textbook-source-list small { display: block; color: var(--color-ink-soft); }
.lesion-actions { display: flex; flex-wrap: wrap; gap: .55rem; align-items: center; }
.lesion-actions .button { margin: 0; }
.source-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 1rem; }
.source-card { min-width: 0; padding: 1.1rem; border: 1px solid var(--color-line); border-radius: var(--radius-lg); background: var(--color-surface); box-shadow: var(--shadow-soft); }

@media (max-width: 760px) {
  .lesion-learning-sequence,
  .normal-background-lesion,
  .unified-lesion-grid { grid-template-columns: 1fr; }
  .source-grid { grid-template-columns: 1fr; }
  .lesion-learning-sequence article::after { top: auto; right: 50%; bottom: -.85rem; content: "↓"; transform: translateX(50%); }
  .unified-lesion-card > summary { flex-direction: column; }
}