New WebUI Play/Pause

Hi All,
I have multiple instances of Kodi running in my home and i want to make a simple WebUI where i can see the poster (either movie or TV Show), its progress and have a Play/Pause button.

The nowPlaying addon i saw on here was kind of the idea, but the progress bar wouldn’t work and it didn’t have any controls. Finished product would be IFRAMES on a webserver with all Kodi devices which have something playing and i could stop them any time.

I cannot find any documentation on how to get started on these web UIs, I have looked at nowplaying and chorus (which is other extreme way too much functionality for what i want) but very few similarities. Please can someone point in correct direction for documentation or an existing addon that i could use for what i want.

Many Thanks
Bighead85