Featured Images in Mansory view overlapping on mobile

Hi,
I have an issue with displaying portfolio images on the mobile devices. It seems to be a problem with images loading slower than site is opening, in other words site is already loaded and images slowly appearing and have no space to fit.
Problem is solved itself when mobile is flipped horisontally and then back vertically.
Is there any solution? Is it problem with gallery or theme?

The page I need help with: [log in to see the link]

 

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