/* CC 风格字幕: 白字 + 黑描边 + 半透明柔和底板，长按可拖动 */
.sub{position:absolute;left:50%;top:94%;transform:translate(-50%,-100%);max-width:92%;text-align:center;white-space:pre-line;line-height:1.3;font-weight:600;color:#fff;font-size:clamp(11px,calc(5cqh*var(--sub-scale)),40px);padding:.15em .55em;border-radius:.45em;background:rgba(0,0,0,var(--sub-bg));backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px);-webkit-text-stroke:.07em #000;paint-order:stroke fill;text-shadow:0 .06em .16em rgba(0,0,0,.7),0 0 .5em rgba(0,0,0,.35);box-shadow:0 .2em .8em rgba(0,0,0,.28);touch-action:none;user-select:none;-webkit-user-select:none;cursor:grab;z-index:3;transition:box-shadow .15s}
.sub:empty{display:none}
.sub.dragging{cursor:grabbing;box-shadow:0 0 0 2px var(--accent),0 .3em 1.2em rgba(0,0,0,.5);transition:none}