The css files have border-collapse: collapse; on the wrong element

In all of the included styles, the popup-element.css file has:

.popup-style-white .popup-element-body table.popup-layout{ margin: 0; padding: 0; position: relative;}
.popup-style-white .popup-element-body table.popup-layout tbody{ border: none; border-collapse: collapse;}
.popup-style-white .popup-element-body table.popup-layout td{ margin: 0; padding: 0;}

The border-collapse: collapse; is a table element attribute not the tbody element. So the code should be:

.popup-style-white .popup-element-body table.popup-layout{ margin: 0; padding: 0; position: relative; border-collapse: collapse;}
.popup-style-white .popup-element-body table.popup-layout tbody{ border: none; }
.popup-style-white .popup-element-body table.popup-layout td{ margin: 0; padding: 0;}