Can you help me find this attribute?

http://img.photobucket.com/albums/v242/C_San/blalh_zpsaa107d52.jpg example.
The issue is the 2nd sublevel of a drop down. It’s got a weird float or something, so that the edges don’t touch, highlighted in blue in the image. But firebug’s just bringing up the “element.style” thing and I have NO idea where this element is to change it. it’s not in my theme or child themes style.css. Where would this element be hiding??