Collection-repeat combined with slide-box on one screen

Hi I’m trying to put a slide-box above a collection of images. Is this possible? I’ve started playing around with a solution, here my codepen:

But I’m encountering some problems. First images are removed from the collection to early, second the last images are not shown respectively the user can’t scroll until the bottom of the page.
Is there something that I’m missing or some conceptual misunderstandings?


I am also having this problem. The first two items in a 3-wide grid are disappearing before they leave the frame, and I can’t get the scroll view to pull the final line of elements high enough to pass the footer.