3 yo peeing on the floor to punish us

Personally I would ignore the behavior . Wait until she leaves the room then clean it up . I also would play it off lightly , like saying " Opps looks like the invisible dog left a surprise , looks like I'll have to put a diaper on the dog " while smiling . If she sees she isn't getting a reaction it might be enough for her to stop :)I'm sure others will post and offer suggestions .:)