Many people are under the impression the entire page is just the top part. It seems to be the case that the buttons reinforce that this is a gallery, and it basically fills the whole page. Ways of making the page shorter:
The overall goal is to make the page shorter so that people see there is a break. Ideally they get a peak at some text (the subtitle our purpose, or ideally part of the title) to see they should scroll down.
Rotate the dots - We can organize the dots vertically on the right hand side of the page, going from top to bottom, This would buy us some space to make the top portion smaller.
The big issue is that the image of shakespear on the second page drops the GIFs down half an inch, as well as the issue with the desk under it. If we can change the background, we can squeeze an inch of space and make it clear that there is more below.
Another solution here is to include a downward pointing arrow where the 3 dots are now to send the user below and indicate there is more. We could move the buttons to the right hand side while still preserving the overall structure of the page. I'm more inclined though to make about 15% of the vertical space grey and the rest the leading color.