How to add a popup to ACPay join page?
 

If I wanted to add an exit popup to my ACPay join page when someone does not click on the join link, how would I go about doing that?

Should I put the join page in an I-frame and add the popup script to the main html page? What else could I do?

I would like to put a popup offering a free trial or something similar if people do not click on the join link.