Things in CSS are sometimes bit tedious to write, especially when it’s comes to CSS3 and those vendor prefixes that exist. But with a mixin it’s lets you make groups of CSS declarations that you want to re-use throughout your site and you can even pass in values to make your mixin more flexible than ever. So for example a good use of a mixin are for vendor prefixes.
You will see that there are countless of mixin libraries available so for this post I have complied a list of useful Sass mixin libraries that are available to help developers to avoid the repetitive things that we do through CSS such as animations, transition effects, adapting browsers and many more.
Andy is meant to be an open-source repository of SASS mixins, so if something seems wrong or if you wish to add your own mixins, please feel free to fork it on Github.