Ok I checked out your app on mobile. I see what you’re aiming at.
Without seeing your actual application, there’s not an easy way to troubleshoot this. As far as I can tell, the popup is behaving properly, there’s just a ton of extra space around the element. That being said, it looks like your problem is coming from the responsiveness of your app, specifically your popup element.
I’d start playing around with responsive settings, such as setting groups to fixed width, using the responsive editor to understand margins and rearranging/defining properties to accommodate, that kind of thing.
Again, it looks as though the popup element is behaving correctly, it’s the responsiveness of your popup element (and/or possibly the other elements) that seems to be causing a large margin on a mobile viewport. Because there’s so much going on, without access to your editor, I can’t guess where your problem is coming from.
Lemme know if that works