Flatsome Theme Chnage Width of Site To Dsiplay Mobile Menu




I am trying to change the width of my site using media queries as to when the mobile menu of the Flatsome theme should show - http://flatsome.uxthemes.com/

Their support are refusing to help. I basically need the mobile menu to show at larger screen sizes, but I am unsure what CSS I need to implement.

Could somebody please help me regarding this. I would really apprentice it.

Many Thanks