Changing color of value using map_state or when

[woobenjamin]

Hi,
I'm having a problem with trying to change the color of the value (not icon) based on a set of parameters.

For example, I want to show the Air Quality Index (AQI)
So, I use something like

- entity: sensor.aqi
  name: AQI

I haven't fully figured out the when or map_state logic yet, but I can read some more, but essentially, what I want to do is show the value of the AQI, for any value <25, it's green, 25 to 50, yellow, and 50+ red.
I don't know how to change the color of the VALUE
If I use value: mdi:icon, I seem to be able to use color: , but for just value, I can't seem to figure it out.

Thanks in advance.