This article was an eye-opener - I write CSS all the damn time and hadn't even clocked box-sizing yet. I don't wanna know how many hours I've spent calculating

This article was an eye-opener - I write CSS all the damn time and hadn't even clocked box-sizing yet. I don't wanna know how many hours I've spent calculating widths-after-padding(-but-wait-it's-different-on-both-sides) and commenting the CSS so other developers know why this element is width: 169px even though the container is 200px... Not to mention: textarea { width:100%; padding:20px; oh shit. }