Testing hamburger menu on mobile

Just looked at the following site on my iphone using safari. The mobile menu once clicked on will open and then after selecting the page it will not close unless I click somewhere else on the screen. Is this only happening to me or there is a way to fix this?

http://themes.xara.com/v11/ultimate/

I can confirm this is the case. You have to click off the menu to close it.

Thank you Egg.