Dynamic aspect ratio

[Andrew-Chen-Wang]

I have a small screen, and, following this tutorial (which is written phenomenally), it would be great to have some way to figure out the aspect ratio and set dimensions based on this (at least within the tutorial).

I'm new to Rust, so it'd be great to see something like this in the future. For any others with small screens, this is made in a 4:3 aspect ratio. I'm also new to graphics, so please lemme know if I'm thinking about this incorrectly. (Also imports could be shown, but I can open some PRs for this).