Is there any way to prevent the menu from collapsing into a hamburger icon on a narrow screen. 

I currently have explicit code in ctat.org.uk to display buttons instead of using the automatic menuing capability.  This allows the buttons to be shown regardless of screen width.  I get feedback from users to say they appreciate this approach.

I would like to use the automatic menuing capabilities, but need some way to prevent the menu changing into a hamburger.