Invert plot color for a more consistent dark mode experience

[ArnaudKunzi]

I implemented a proof of concept to invert colors in the plot to have a consistent dark-mode experience.

This can be toggled on/off with a left click on the plot or smoothly activated with a wheel event.

https://github.com/ArnaudKunzi/darkstudio

Is there any interest to upstream the functionality? (The JS code is hacky/amateurish, so it would probably need a rewrite.)