iPad jumps to the left when last menu item on right is press.

iPad jumps to the left when last menu item on right is press.

I am having a problem with the iPad version of website. When I press the last menu item to my right the ipad my page content move to the left then go back to normal.

The website url is http://www.darbysdestinations.com, you must be on an iPad to see this happen.
I have tried the web simulator does not work.

If you click on the about us you will see the problem