How to Eliminate Navigation Menu Wrapping

Using Scribe and Upfront editor...

In edit mode the top navigation menu looks fine:
https://www.dropbox.com/s/dyv9nrd54i6u0ne/Screenshot%202015-06-10%2020.45.46.png?dl=0

But when saved and live at full screen size the last menu item wraps:
https://www.dropbox.com/s/dyv9nrd54i6u0ne/Screenshot%202015-06-10%2020.45.46.png?dl=0

Please let me know how to fix this.

Thanks in Advance,
Stephan