Animation effect on gallery

Hi all. I’m trying to animate a gallery to give it an effect like this, so they snap up as you scroll http://www.robot-food.com/work/

I’m trying by using this code but it’s not working. Any pointers? Can you apply animation to a gallery? Thanks.

export function galleryHome_viewportEnter() {
} $w(" #galleryHome ").show(“fadeIn”);