Getting responsive error on phones

My web link with GitHub-Page: ampueus . github . io/superliga

When I design the web (using the developer tools) in the browser (Firefox) it looks fine, but when I open it on the phone, it fits badly (I have tested it with an android and an iphone) .

With browser’s DevTools → style-With-Dev-Tools-Via-Browser — ImgBB
With real phone → style-With-Real-Phone — ImgBB

Any idea why this is happening?