:buffering
Targets media elements (like <video> or <audio>) while they are actively loading data and currently 'buffering'.
Quick example
video:buffering {
/* Adds a subtle visual cue that the video is loading */
outline: 2px solid rgba(255, 255, 255, 0.5);
opacity: 0.8;
}:buffering Browser Support
Limited availability 13% global usage
This feature is not Baseline because it does not work in some of the most widely-used browsers.
Not ready for production without a fallback.
15.4+