Overlay skin too large

When I choose one of the overlay skins (animation while loading filtered product) they are filling almost the entire screen.

Is this default and if so: how can reduce the size of it?
Or is this a compatibility issue with my theme?

I have switched off the overlay skin for now, but this is what it looks like:

https://speedpedelecreview.com/wp-content/uploads/2022/02/Overlay-skin.png

Can you please advise?

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