Change background colour of the icon box

Hi

I am trying to change the background colour of the icon box (flipping box style).
This includes the background before flipping the box over as well as the background of the flipped over box.

I can’t seem to find the styling of the icon box in the CSS file of the theme to change the styling.

Where can I change the background colours of the icon box.

Thank you! Your help will be greatly appreciated.

Kind Regards

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