PV panels - colored "heatmap panels"

Hi all, I want to create a dashboard with my PV panels in some sort of a “heatmap”.

e.g. 0-300W where 0 is white and 300 is red and all kinds of colours between.

What would be a start is to have a picture/glance card of some sort of template entity that colours between 0-300.

I tried to search but might not have given the right terms but unable to find.
Thanks in advance!