.lecture-source-panel {
  margin-top: 1rem;
  padding: clamp(1rem, 2vw, 1.35rem);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(135deg, rgba(32, 215, 255, 0.08), transparent 38%),
    linear-gradient(225deg, rgba(82, 230, 172, 0.07), transparent 42%),
    var(--surface);
  box-shadow: 0 18px 44px var(--shadow);
}

.lecture-source-panel-head {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1rem;
}

.lecture-source-panel-head h2 {
  margin: 0.25rem 0 0.35rem;
  font-size: clamp(1.25rem, 2vw, 1.7rem);
}

.lecture-source-panel-head p {
  max-width: 62rem;
  margin: 0;
  color: var(--muted);
}

.lecture-source-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(18rem, 1fr));
  gap: 0.9rem;
}

.lecture-source-card {
  min-width: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.045);
}

.lecture-source-card-head {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.8rem;
  align-items: start;
  padding: 0.85rem;
  border-bottom: 1px solid var(--line);
}

.lecture-source-card-head h3 {
  margin: 0 0 0.55rem;
  font-size: 1rem;
  line-height: 1.25;
}

.lecture-code {
  display: inline-flex;
  min-width: 3.6rem;
  min-height: 2rem;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line-strong);
  border-radius: 6px;
  background: color-mix(in srgb, var(--accent) 13%, transparent);
  color: var(--text);
  font-size: 0.78rem;
  font-weight: 900;
}

.lecture-topic-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.lecture-topic {
  display: inline-flex;
  min-height: 1.65rem;
  align-items: center;
  padding: 0.18rem 0.5rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 750;
}

.lecture-source-figures {
  display: grid;
  gap: 0.75rem;
  padding: 0.85rem;
}

.lecture-source-figure {
  min-width: 0;
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(2, 7, 18, 0.55);
}

.lecture-source-figure img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: contain;
  background: #050914;
}

.lecture-source-figure figcaption {
  display: grid;
  gap: 0.35rem;
  padding: 0.65rem 0.75rem 0.75rem;
  color: var(--muted);
  font-size: 0.86rem;
  line-height: 1.45;
}

.lecture-source-figure figcaption span {
  color: var(--accent-3);
  font-size: 0.72rem;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.lecture-week-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(12rem, 1fr));
  gap: 0.75rem;
}

.lecture-week-card {
  min-height: 8.5rem;
  display: grid;
  gap: 0.35rem;
  align-content: start;
  justify-items: start;
  padding: 0.85rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.045);
  color: var(--text);
  text-align: left;
}

.lecture-week-card:hover,
.lecture-week-card:focus-visible {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px color-mix(in srgb, var(--accent) 40%, transparent);
}

.lecture-week-card small {
  color: var(--muted);
  line-height: 1.35;
}

html[data-theme="light"] .lecture-source-panel {
  background:
    linear-gradient(135deg, rgba(5, 103, 255, 0.08), transparent 38%),
    linear-gradient(225deg, rgba(0, 143, 109, 0.07), transparent 42%),
    var(--surface);
}

html[data-theme="light"] .lecture-source-card,
html[data-theme="light"] .lecture-week-card {
  background: rgba(255, 255, 255, 0.76);
}

@media (max-width: 760px) {
  .lecture-source-panel-head {
    display: grid;
  }

  .lecture-source-grid,
  .lecture-week-grid {
    grid-template-columns: 1fr;
  }

  .lecture-source-card-head {
    grid-template-columns: 1fr;
  }
}