.container{max-width:580px;position:relative;}
video{width:100%;height:auto;background:#000;display:block}
#overlay{position:absolute;border:2px dashed #2563eb;width:180px;height:180px;cursor:move;user-select:none;display:none}
#overlay .handle{position:absolute;width:14px;height:14px;background:#2563eb;border-radius:50%;right:-7px;bottom:-7px;cursor:se-resize}
body{font-family:system-ui,sans-serif;margin:2rem}