Ask HN: Custom Painting Parts of Code?

I want to paint parts of my code a different color to identify functions and parts visually.

For example on a JSON im editing i would like to select an object and right-click to change the color - making the linter theme for example more red or making the background red.

I'm interested in how to do this on vscode but also on opinions on the utility of this type of thing. I come from music producing and there its very important to color each part to conceptually draw a picture, but seems like in the programming world we just want to do it automatically / based on rules