PostCSS is a tool for transforming styles with JS plugins. These plugins can lint your CSS, support variables and mixins, transpile future CSS syntax, inline images, and more.
[2] PostCSS - a tool for transforming CSS with JavaScript ( ()) http://postcss.org/
[4] GitHub - posthtml/posthtml-content: Apply functions to tags through custom attributes, https://github.com/posthtml/posthtml-content