How to use global mixins and variables with CSS Modules in React with SASS

Global mixins and variables with CSS modules in React with SASS

These days it’s fairly common to use different CSS frameworks or libraries to handle styling in a React app such as Tailwind or styled-components. Typically I tend to prefer more traditional CSS with separated files. Outside of the arguments of why this may be preferred or not it’s still fairly useful to have a set of global mixins (SASS) and/or variables to keep it DRY.

Starting an app with Create-React-App or next a fairly common option is to use CSS Modules which guarantees that the styles per component will not have any conflicts, however, it does mean it’s slightly different to access these global variables.

This tutorial assumes you already have a react app ready to configure.

The package

Create-react-app docs recommend using node-sass for the styling, however, this is deprecated so I would suggest using sass (Dart Sass) as it is still actively receiving support. This can be quickly done with:

yarn add sass

npm install sass

The stylesheet

Now with that out of the way let’s create a file for our mixins with the name _variables.scss:

variables

Mixin stylesheet

In the actual style sheet, it can be imported in the following way (any file *.module.scss):

stylesheet

Imported mixins

Variables

For variables it would be something very similar, let’s have a file with the name _variables.scss:

variables

Variable stylesheet

And importing it can be done in a similar fashion:

stylesheet

This can be quite useful to reuse a lot of variables and similar styles throughout the entire project while still maintaining the module structure.

For example, I did something along these lines to share variables to use in media queries throughout my project:

Example stylesheet

This is quite useful as I used a combination of CSS variables and SASS variables to reuse a lot of fixed sizes and paddings to keep everything standardized throughout the entire app.

And that’s it! If you have any questions let me know in the comments below.