So, I had such a problem with FancyBox when, when scrolling the body of the page (main page), the field shifts left and up in a random order.
Attached GIF to demonstrate the problem:

I use Fancybox v2 as far as I know.
The website is here (under the "daily training" tab).
This is the code I use to call fancybox:
$(".signup").fancybox({ maxWidth: 800, maxHeight: 600, fitToView: false, width: '70%', height: '70%', autoSize: false, closeClick: false, openEffect: 'none', closeEffect: 'none' });
I checked their API, but could not understand what makes the position "dance".
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EDIT
So I managed to isolate the problem. when I add "openEffect:" none "everything goes against it. Without it, the box remains static and sticks to the upper left side of the screen.
any further ideas?
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