.lesson-player{border:1px solid var(--color-line);border-radius:var(--radius-card);background:var(--color-surface);color:var(--color-ink);outline:none;overflow:hidden}.lesson-player:focus-visible{box-shadow:0 0 0 3px var(--color-steel)}.lesson-player__mirror-notice{padding:var(--space-2) var(--space-4);background:var(--color-vermilion);color:#fff;text-align:center;font-size:.875rem;font-weight:700}.lesson-player__stage{aspect-ratio:848/464;background:#111;place-items:center;display:grid;overflow:hidden}.lesson-player__stage video{object-fit:contain;width:100%;height:100%}.lesson-player__stage.is-mirrored video{transform:scaleX(-1)}.lesson-player__error{max-width:40rem;padding:var(--space-8);color:#fff;text-align:center}.lesson-player__error p{margin:var(--space-2) 0 var(--space-4);color:#dedede}.lesson-player__error a{color:#fff}.lesson-player button,.lesson-player input{touch-action:manipulation}.lesson-player button{cursor:pointer}.lesson-player button:disabled{cursor:not-allowed;opacity:.42}.lesson-player button:focus-visible,.lesson-player input:focus-visible{outline:3px solid var(--color-steel);outline-offset:2px}.lesson-player__primary-controls,.lesson-player__learning-controls,.lesson-player__status{gap:var(--space-2);padding:var(--space-3);border-top:1px solid var(--color-line);align-items:center;display:flex}.lesson-player__segment-list{border-top:1px solid var(--color-line);max-height:28rem;overflow-y:auto}.lesson-player__segment-list ol{margin:0;padding:0;list-style:none}.lesson-player__segment-list li{border-bottom:1px solid var(--color-line)}.lesson-player__segment-list button{gap:var(--space-3);width:100%;min-height:48px;padding:var(--space-2) var(--space-4);background:var(--color-surface);color:var(--color-ink);text-align:left;border:0;border-left:4px solid #0000;border-radius:0;grid-template-columns:4.5rem minmax(0,1fr);align-items:center;display:grid}.lesson-player__segment-list button>span{color:var(--color-steel);font-variant-numeric:tabular-nums;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:.8125rem}.lesson-player__segment-list li.is-active button{border-left-color:var(--color-vermilion);background:var(--color-vermilion-soft)}.lesson-player__segment-list strong{font-weight:600}.lesson-player__primary-controls{background:var(--color-ink);color:#fff;flex-wrap:wrap}.icon-button,.tool-button,.lesson-player__ab-controls button,.segmented-control button{border:1px solid var(--color-line);border-radius:var(--radius-control);background:var(--color-surface);min-width:44px;min-height:44px;color:var(--color-ink);font:inherit;justify-content:center;align-items:center;display:inline-flex}.icon-button svg,.tool-button svg{width:20px;height:20px}.icon-button--primary{border-color:var(--color-vermilion);background:var(--color-vermilion);color:#fff}.lesson-player__primary-controls>.icon-button:not(.icon-button--primary){color:#fff;background:#272927;border-color:#555}.lesson-player__timeline{flex:15rem;align-items:center;min-height:44px;display:flex}.lesson-player__timeline input,.lesson-player__volume input{width:100%;accent-color:var(--color-vermilion);cursor:pointer}.lesson-player__time{font-variant-numeric:tabular-nums;text-align:center;min-width:7.75rem;font-family:ui-monospace,SFMono-Regular,Consolas,monospace;font-size:.8125rem}.lesson-player__volume{align-items:center;width:5rem;min-height:44px;display:flex}.lesson-player__learning-controls{flex-wrap:wrap;align-items:flex-end}.segmented-control{border:0;margin:0;padding:0;display:inline-flex}.segmented-control legend{margin-bottom:var(--space-1);color:var(--color-ink-soft);font-size:.75rem}.segmented-control button{border-radius:0;min-width:52px}.segmented-control button:first-of-type{border-radius:var(--radius-control) 0 0 var(--radius-control)}.segmented-control button:last-of-type{border-radius:0 var(--radius-control) var(--radius-control) 0}.segmented-control button+button{margin-left:-1px}.segmented-control button[aria-pressed=true],.tool-button[aria-pressed=true]{border-color:var(--color-pine);background:var(--color-pine);color:#fff}.lesson-player__tool-group,.lesson-player__ab-controls{gap:var(--space-2);display:flex}.tool-button{gap:var(--space-2);padding:0 var(--space-3)}.lesson-player__ab-controls button:not(.icon-button){padding:0 var(--space-3)}.lesson-player__status{min-height:48px;color:var(--color-ink-soft);flex-wrap:wrap;justify-content:space-between;font-size:.875rem}@media (width<=767px){.lesson-player__primary-controls{gap:var(--space-2)}.lesson-player__timeline{flex-basis:100%;order:-1}.lesson-player__time{margin-right:auto}.lesson-player__volume{display:none}.tool-button span{font-size:.8125rem}}@media (prefers-reduced-motion:reduce){.lesson-player *,.lesson-player :before,.lesson-player :after{scroll-behavior:auto!important;transition:none!important}}