There's more to it than what Sass, Less and co. can provide. It simplifies dynamically changing a bunch of CSS properties from JavaScript a lot. Instead of chan

There's more to it than what Sass, Less and co. can provide. It simplifies dynamically changing a bunch of CSS properties from JavaScript a lot. Instead of changing all the elements using a particular style, you could now change just the variable instead. This gets even more interesting when properties are composed of variables, like gradient colors. Also, this is a pretty high-level addition. I wouldn't be surprised if someone came up with a polyfill for this soon.