Lets add a border to a row in Divi. For this example I have added custom css to the row module. This will style the row container that holds its columns and modules. I’ve added a simple border and some custom padding to add a nice box around the contents of the row. This tip was a CSS tip by Elegant Themes that I had read.

Row Settings -> Custom CSS –> Main Element
border: 3px solid #74c403;
padding: 20px;

This tip was featured on Elegant Themes blog.
Elegant Themes Tips