Please take a look at this URL ( After finish the loading screen ) (https://cdn.htmlgames.com/HiddenClassroom/)

On every screen this web-page takes full height and there is no change on any element in any screen. Even if I zoom in or zoom extremely the website doesn't feel any change.

How can I achieve that with JavaScript, CSS & HTML so that my website stay consistent? Even I zoom that shouldn't change how it look.

Target: Make fit to all screen size and zoom like https://cdn.htmlgames.com/HiddenClassroom/

Tried: I tried to listen window resize and transform: scale(width/maxWidth) the whole website on every resize but it's not giving the desired result.