When you need a popup inside of the Divi Theme it can be a little tricky to make the content inside the popup look great. With the Divi Overlay plugin you can use the Divi builder to make ANYTHING you want in the popup. Put a form in it, a login area, contact info, a map, an email capture, truly anything you want. Kori Ashton from https://askkori.com shows you step-by-step how to use the Divi Overlay WordPress plugin.
Here’s the link to the Divi Overlay Plugin