I'm currently using version 2.2.12 and the standalone CSS video component in the video.css seem to be different than the one in the the full semantic.css file.
I didn't make a full diff check, however, for example, I can see that the .ui.embed block is missing, and the version seem to be stuck to 2.0.0.
It looks like this issue is affecting multiple files and for multiple versions from 2.0.0 to 2.3.3: colorize.js, colorize.min.js, video.css, video.min.css, video.js, video.min.js, visit.js and visit.min.js.
example: https://cdnjs.cloudflare.com/ajax/libs/semantic-ui/2.2.12/components/video.css