Change state color from yellow to something else

Configuration
1

I have an entity card showing a binary sensor of my window if it’s open or not.
It works just fine and show when it opens and closes and changes icon accordingly.
However, I would like it to not change to a yellow color when it’s open.

Right now it looks like this:
When closed:
image
When open:
image

I read a couple of threads saying something about --paper-item-icon-color like in the example below:

      - type: state-icon
        tap_action: more-info
        entity: binary_sensor.window
        style:
          top: 85%
          left: 53%
          "--paper-item-icon-color": green

However I haven’t got it to work and I’m not really sure where to put the code. Is it in the entity card? Or in configuration.yaml for the entity? Or somewhere else?
Or can it be done some other way?