Hi. I am creating a child theme using Studio Press's Genesis.

I have a top category which has many sub-cats - too many to display in a simple drop down menu from a nav bar. So I would like the sub-cats to display in a wide wrap with, say, 3 columns.

I am presuming that this would not be possible simply be .css. The only plugin I found was one that worked with a widget rather than the main Appearance > Menu setup.

Can anybody point me in the right direction to do this?