Can I resize an iframe with a video in it, if other stuff on my page takes too much room?

Can I resize an iframe with a video in it, if other stuff on my page takes too much room?

I have page that shows a video, but also shows various text and other controls beneath it.  I can't control how much vertical space these take - it varies.

So I'd like to give the user two buttons - a enlarge-video button,and a shrink-video button.

These would expand the video (I assume by expanding the iframe).

I also have other pages that have the same problem, but they use a video-tag instead of an iframe

Is there a way to just set CSS height of an iframe and/or a video-tag?

Thanks.
Gid