Toggle light on specific key press

I've assigned an action key to my mute button so that when it is pressed the light changes to red. Or at least that is my goal.



At the moment it's using a solid red light that I've created however the issue is that there's a duration on it, and after a while it changes back to it's original color.



How do it set it to remain red when pressed and terminate the macro once it 's pressed again?