weird highlight on first option on menu bar - Dixi

The customised menu bar of my blog (using WPMU Dixi) is great - so easy to use! Thank you! Just one thing - the first menu item on the bar has a bunch of blank space next to it before the next menu item shows. And when I hover over it, the hover colour is a dark grey - not part of my menu selections at all. How can I fix this?

see here: