Mobile menu interfering with desktop display

Hi The main navigation menu on my site http://thakehamparish.co.uk/ has a problem since updating to theme v.3 today. The mobile mini menu buttons are now intruding into (top & bottom of) my main nav menu although I am viewing the site via a desktop monitor. How can I fix this? Does it mean having to revert to v.2.9.2 (& if so, how)? Thanks!