Somehow we forgot how to center rectangles and must find our way back

Centering things in CSS is the poster child of CSS complaining. Why does it have to be so hard? They jeer. I think the issue isn't that it's difficult to do,

If you make a div with overflow:scroll;transform:skewX(45deg); and give it a child element with transform:skewX(-45deg); you can make a diagonal scroll bar. It seems pretty useful if you want to hurt people's eyes.