til / rotate in CSS with turn

There are several ways¹ to rotate items using CSS. The most common is using degrees (deg), to describe rotations from 0 to 360. Another option is radians (rad), which uses values from 0 to 2π. But, a more intuitive approach that doesn’t involve math terms is to use turns (turn)².

Even though I was unaware of this until yesterday, browser support is great³, even IE 9 supports it.