[SOLVED] left sidebar, gray block from 1st level appears in front of 2nd level menu i

I have several 2nd level menu items. On the left sidebar, the gray block in front of the next 1st level menu item goes up too far and shows up in front of all but the first of the 2nd level items. Looks like a bug to me. I've looked through the forum, but can't find a solution. Surely someone else has seen this! Thanks for your help!
The site is www.denvergolfhomes.com