Hover and active states

Hi,

Please can you help, I have managed to change the colour of my button (blue) under “Style of labels, field inputs, buttons, and text”.

I now what to find out how I can change the button so that it goes from blue to grey when I hover on it to a darker grey when I actually click on it.

Im am not sure where to actually make the change so that my button does change colour.

Thanks for your time, all the best, Cayleigh