Animating scrollTop is quite a common effect that some developers/designers add (personally I'm not a fan). Usually it's done using the jQuery animate function

Animating scrollTop is quite a common effect that some developers/designers add (personally I'm not a fan). Usually it's done using the jQuery animate function, meaning you can't take advantage of CSS transitions. As you can't add a CSS transition onto the window scroll, this demo is useful as it shows a workaround that achieves the same effect using CSS transitions.