CSS Nesting Module
This looks <i>awesome</i>. I'm so glad they re-used the & syntax popular in many compile-to-CSS languages. Between this and CSS variables, I might not even need SASS in my toolchain anymore, which would be amazing.<p>@nest looks extremely cool too. An easy way to keep rules affecting one selector logically grouped with it, even if the selector relies on a small thing about its parent elements.