I have run this locally, and the menu hovers are smooth. But when I run the exact same pages remotely, they bounce.... especially on the coffee version. (See the icons at the bottom of the page for the orange and blue versions. The Orange version is really bouncey.)
Can you look at it and see if there is something that can be done to make it smooth like it is locally. You don't even notice an image bounce locally, but remotely, it disappears the image and then reappears, looking bouncy.