.bc-video-stack{
  display:grid;
  gap:18px;
  margin:24px 0 34px;
}

.bc-video-card{
  overflow:hidden;
  border:1px solid var(--border-strong,#c6d1ca);
  border-left:4px solid var(--accent,#1f6652);
  border-radius:8px;
  background:var(--bg-card,#fff);
  color:var(--text-primary,#1c1917);
  box-shadow:0 12px 30px rgba(18,63,51,.08);
  font-family:var(--font-body,'Source Sans 3','Noto Sans SC',sans-serif);
}

.bc-video-summary{
  display:flex;
  justify-content:space-between;
  gap:24px;
  align-items:center;
  min-height:88px;
  padding:18px 20px;
  cursor:pointer;
  list-style:none;
}

.bc-video-summary::-webkit-details-marker{display:none}
.bc-video-summary::after{
  content:'+';
  flex:0 0 auto;
  color:var(--accent,#1f6652);
  font:500 27px/1 var(--font-display,serif);
}
.bc-video-card[open]>.bc-video-summary::after{content:'−'}
.bc-video-summary:focus-visible,
.bc-video-card button:focus-visible,
.bc-video-card select:focus-visible,
.bc-video-card a:focus-visible,
.bc-video-card video:focus-visible{
  outline:3px solid rgba(37,99,235,.32);
  outline-offset:3px;
}

.bc-video-summary-copy{display:grid;gap:3px;min-width:0}
.bc-video-route{
  color:var(--accent,#1f6652);
  font-size:11px;
  font-weight:800;
  letter-spacing:.08em;
}
.bc-video-summary-copy strong{
  color:var(--text-primary,#1c1917);
  font:600 clamp(20px,2.2vw,27px)/1.18 var(--font-display,'Playfair Display','Noto Sans SC',serif);
}
.bc-video-summary-copy small,
.bc-video-trigger small,
.bc-video-evidence-note span{
  display:block;
}
.bc-video-summary-copy small{
  margin-top:4px;
  color:var(--text-secondary,#57534e);
  font:500 14px/1.35 var(--font-body,'Source Sans 3','Noto Sans SC',sans-serif);
}
.bc-video-trigger{
  flex:0 0 min(180px,25%);
  color:var(--accent,#1f6652);
  font-size:12px;
  font-weight:700;
  text-align:right;
}
.bc-video-trigger small{margin-top:2px;color:var(--text-muted,#6b7280);font-weight:500}

.bc-video-body{padding:0 20px 22px;border-top:1px solid var(--border,#e2e8e4)}
.bc-video-objective{max-width:74ch;margin:18px 0;color:var(--text-secondary,#57534e);font-size:16px;line-height:1.62}
.bc-video-frame{
  position:relative;
  overflow:hidden;
  aspect-ratio:16/9;
  border:1px solid var(--border-strong,#c6d1ca);
  border-radius:7px;
  background:#111;
}
.bc-video-frame video{display:block;width:100%;height:100%;object-fit:contain;background:#111}
.bc-video-load{
  position:absolute;
  left:50%;
  top:50%;
  min-width:220px;
  min-height:58px;
  transform:translate(-50%,-50%);
  border:1px solid rgba(255,255,255,.78);
  border-radius:999px;
  background:rgba(18,63,51,.94);
  color:#fff;
  cursor:pointer;
  font:700 15px/1.25 var(--font-body,'Source Sans 3','Noto Sans SC',sans-serif);
  box-shadow:0 8px 22px rgba(0,0,0,.22);
}
.bc-video-load span{display:block;margin-top:2px;font-size:12px;font-weight:500;opacity:.82}
.bc-video-load:hover{background:#174f41}
.bc-video-card.is-media-loaded .bc-video-load{display:none}

.bc-video-controls{
  display:flex;
  flex-wrap:wrap;
  gap:10px;
  align-items:end;
  padding:14px 0;
  border-bottom:1px solid var(--border,#e2e8e4);
}
.bc-video-controls label{display:grid;gap:5px;color:var(--text-muted,#6b7280);font-size:11px;font-weight:700}
.bc-video-controls select,
.bc-video-controls button,
.bc-video-checkpoint,
.bc-video-transfer{
  min-height:42px;
  border:1px solid var(--border-strong,#c6d1ca);
  border-radius:5px;
  background:#fff;
  color:var(--text-primary,#1c1917);
  font:700 13px/1.25 var(--font-body,'Source Sans 3','Noto Sans SC',sans-serif);
}
.bc-video-controls select{min-width:92px;padding:8px 30px 8px 10px}
.bc-video-controls button{padding:9px 13px;cursor:pointer}
.bc-video-controls button[aria-pressed='true']{border-color:var(--accent,#1f6652);background:var(--accent-bg,rgba(31,102,82,.07));color:var(--accent,#1f6652)}

.bc-video-chapters{padding:18px 0 4px}
.bc-video-chapters h3{margin:0 0 10px;color:var(--text-primary,#1c1917);font:600 17px/1.3 var(--font-display,serif)}
.bc-video-chapters>[data-chapter-list]{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:7px}
.bc-video-chapter{
  display:grid;
  grid-template-columns:28px minmax(0,1fr) auto;
  gap:9px;
  align-items:center;
  min-height:54px;
  padding:8px 10px;
  border:1px solid var(--border,#e2e8e4);
  border-radius:5px;
  background:#fbfaf6;
  color:var(--text-primary,#1c1917);
  text-align:left;
  cursor:pointer;
}
.bc-video-chapter:hover{border-color:var(--accent-soft,#91ad9f);background:var(--accent-bg,rgba(31,102,82,.07))}
.bc-video-chapter>span{display:grid;width:27px;height:27px;place-items:center;border-radius:50%;background:var(--accent,#1f6652);color:#fff;font-weight:800}
.bc-video-chapter b{overflow:hidden;font-size:13px;line-height:1.2;text-overflow:ellipsis}
.bc-video-chapter small{display:block;margin-top:3px;color:var(--text-muted,#6b7280);font-size:11px;font-weight:500}
.bc-video-chapter time{color:var(--text-muted,#6b7280);font:600 11px var(--font-mono,'JetBrains Mono',monospace)}
.bc-video-loading,.bc-video-unavailable{grid-column:1/-1;margin:5px 0;color:var(--text-muted,#6b7280);font-size:13px}

.bc-video-actions{display:flex;flex-wrap:wrap;gap:10px;margin-top:14px}
.bc-video-checkpoint,.bc-video-transfer{display:inline-flex;align-items:center;justify-content:center;padding:10px 15px;text-decoration:none;cursor:pointer}
.bc-video-checkpoint:disabled{cursor:default;opacity:.66}
.bc-video-transfer{border-color:var(--accent,#1f6652);background:var(--accent,#1f6652);color:#fff}
.bc-video-transfer:hover{background:#174f41;color:#fff}
.bc-video-evidence-note{margin:13px 0 0;color:var(--text-muted,#6b7280);font-size:12px;line-height:1.45}

.bc-video-card[data-caption-size='small'] video::cue{font-size:78%}
.bc-video-card[data-caption-size='medium'] video::cue{font-size:100%}
.bc-video-card[data-caption-size='large'] video::cue{font-size:126%}
.bc-video-card[data-caption-background='solid'] video::cue{background:rgba(7,18,16,.9);color:#fff}
.bc-video-card[data-caption-background='soft'] video::cue{background:rgba(7,18,16,.58);color:#fff}
.bc-video-card[data-caption-background='clear'] video::cue{background:transparent;color:#fff;text-shadow:0 1px 3px #000,0 0 2px #000}

@media(max-width:760px){
  .bc-video-stack{margin:18px 0 26px}
  .bc-video-card{border-left-width:3px;border-radius:6px}
  .bc-video-summary{align-items:flex-start;min-height:76px;padding:15px 14px;gap:10px}
  .bc-video-trigger{display:none}
  .bc-video-body{padding:0 12px 16px}
  .bc-video-objective{font-size:15px}
  .bc-video-load{min-width:0;width:76%;min-height:50px}
  .bc-video-controls{align-items:stretch}
  .bc-video-controls label{flex:1 1 44%}
  .bc-video-controls select,.bc-video-controls button{width:100%}
  .bc-video-chapters>[data-chapter-list]{grid-template-columns:1fr}
  .bc-video-actions{display:grid}
  .bc-video-checkpoint,.bc-video-transfer{width:100%}
}

@media(prefers-reduced-motion:reduce){
  .bc-video-card *{scroll-behavior:auto!important;transition:none!important}
}