WordPress acts differently when logged

Hello guys, i was working with theme SYDNEY on website: atelierorigin.com, my main goal was to get rid of everything and keep the front page with slider only and all the other pages had to be just regular fullwidth pages.

I must have made some mistake and when I am logged in, in customization menu website acts correctly withou any problem, also when I am logged in and on the website it acts correctly too, the problem begins when I am logged out on other pages, not front page.

Whene there are pictures while loading they are shown down and then they just jump for about 200px up and stay there behind that black bar, also when there is writing it show normally while loading and then it jumps behind that black bar.

Do you know why this website acts differently and where the problem can be guys ?

Thanks a lot !