Horizantal subnav menu

Hello. I am having a hard time making my header subnav menu look and work the way I need.

I am using the menu creator in the admin to add a sub menu to the main header menu.

I am trying to make it horizontal and it is just not working. I feel like the submenu should be in a separate container to work right.

Here is a link to see what I have: https://dev.longviewsources.com/jlb/collection/spring14/spring-1401/

When the submenu comes into view it is affecting the links in the main nav moving them to the right.

Anyone have an idea of how to make the subnav come out without affecting the layout?

Thanks!