Boring cards

Hi again
I’m currently in the process of making my dashboard look a lot more exciting however I’m struggling to change the colour of my plugs from a boring dark blue for off and yellow for on.
I dont want anything really flash just yet but just to change the colour.
I’m using a grid card configuration with the following code but would like the colour to change.
show_name: true
show_icon: true
type: button
tap_action:
action: toggle
entity: switch.garage_fridge_lamp_socket
icon: mdi:power-socket-uk
name: Garage Fridge Lamp
show_state: true

Any ideas or code I can put in to change this

TA