I have removed the custom css on your site, it doesn’t work. I have change PHP file of pagebuilder on your admin. The image size should be fit screen now. Please use Fullwidth > Half to build this kind of layout, the parallax ratio must be set as 0.1. Please check About and Design-retail, I have reset ratio for the 2 pages.
(Plz don’t use fullwidth block + single image, the custom css not for fullwidth block).