Hi,
I agree with you it should not have nested panels with modulecontent class. This is now fixed in the source code repository.
Note however that you can remove the border on the inner div without need for any new ids or classes like this:
.modulecontent .modulecontent { border:none; }
The above selector selects an element with the class modulecontent that is inside another element with the class modulecontent.
Best,
Joe