Plugins that need to extend the Craft CMS Control Panel can use this library and import _mixins.sass from their Sass files, giving them the same mixins and variables used by core Control Panel templates.

Installation via npm is recommended.

npm install craftcms-sass --save-dev

Import the mixins into your Sass files with the @import directive:

@import "../node_modules/craftcms-sass/mixins";

(The exact path will vary depending on where your node_modules folder is in relation to your Sass file.)