CSS grid compatibility for iOS

I have a strange issue that a design I did using CSS grid is not displaying properly on iOS devices, irrespective of the browser (Safari, Chrome, etc). On the other hand, the grid is displayed normally on Android devices. Is there a particular incompatibility between the operational system and this CSS rule? If you are an iPhone owner and you want to test, the page I am talking about is this: https://may4eto.github.io/gallery/ (the images appear stretched out vertically). I tried changing the viewport settings in the HTML and used autoprefixer for the CSS but still doesn't work.