Radio button in PHP

Question

Hi Friends......

I have four radio button(red,green,blue,yello) and one ok button in a form in PHP. I want, when we select any one radio button i.e. red or someone and click ok button then color of the form will change according to select radio button. Suppose that we select red radio button then ok , color of the form will be red.

So please tell me anyone how to do this ?




Thank,.....