Hi, I have an almost fresh install of Drupal Commerce with Kickstart Omega. When I shrink the screen down, the menu disappears and it doesn't show on a mobile device.

My website is: http://eciggie.com.au

I have done some small modifications, but I think it's something to do with the settings in appearance . I have had a look around an am not sure where to go from here.

Thank you
Tom