Using environment variables in theme

[samEngineering]

Greetings ^_^
Is anyone aware of a way to use environment variables in a custom theme file?
I'm trying to do something like this:

theme[cpu_box]="${GREEN}"

If this functionality is not available, this would be a great feature :) btop++ ftw!
Thanks in advance.

[wimstefan]

That would be great!
Another idea is to get the colours via xrdb similar to polybar ...