Colours of the GPG signature verification

[bravoecho]

I would like to customise the look of the GPG signature verification section, and I could not find a suitable option for it. I checked and git itself doesn't have a colour group for it.

It seems to be printing a failed signature verification in normal foreground over ANSI red...

...and a verified signature in cyan over normal background.

I also tried to add this mapping to my delta configuration, to no avail:

[delta "myfeature"]
  map-styles = normal red => purple normal

Thank you for reading my request!