Also `box-sizing: border-box` was how IE designed CSS box sizing (to be simpler to math for the CSS writer rather than simpler math for the Renderer programmer). The fact that it is now just about "required" boilerplate in most CSS reset/normalization steps to throw in a `* { box-sizing: border-box; }` rule to opt in to "do it the IE way" is a massive, vestigial, lasting testament to IE's innovation in CSS in the early CSS standards.
