Sass - Syntatically Awesome Style Sheets
Bourbon - Bourbon - A simple and lightweight mixin library for Sass / CSS.
PostCSS - Increase code readability. Add vendor prefixes to CSS rules using values from Can I Use. Autoprefixer will use the data based on current browser popularity and property support to apply prefixes for you.
Stylus - EXPRESSIVE, DYNAMIC, ROBUST CSS
jQuery - The Write Less, Do More, JavaScript Library.
CSS Next - Use tomorrow’s CSS syntax, today.