Cast Chrome tab to my Android phone

Question

I know it's possible to cast an Android to my PC, or to a Chromecast. I also know it's possible to share my PC with my Android via the Chrome Remote Desktop app.

I want to do the reverse: cast my Chrome screen (and only my Chrome screen) to my phone. This is because I work on my laptop and like to watch videos (e.g. game streams) on Chrome (none of the ones I watch are on Youtube or anything with a similar app).

But I do all my work in a different program so I can't watch Chrome at the same time (my laptop is tiny and I don't have another monitor).

So I want to watch my game streams on my phone but I can't find any way to do that. The closest thing I've found is the Chrome Remote Desktop app, but as soon as I alt-tab away from the video to my work, the phone does the same thing.

I can't figure out how to either a) just cast the Chrome tab to my phone, or b) set up Chrome Remote Desktop so that it only "looks" at Chrome and no other window.