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Adding a Sass Stylesheet

Note: this feature is available with react-scripts@2.0.0 and higher.

Generally, we recommend that you don’t reuse the same CSS classes across different components. For example, instead of using a .Button CSS class in <AcceptButton> and <RejectButton> components, we recommend creating a <Button> component with its own .Button styles, that both <AcceptButton> and <RejectButton> can render (but not inherit).

Following this rule often makes CSS preprocessors less useful, as features like mixins and nesting are replaced by component composition. You can, however, integrate a CSS preprocessor if you find it valuable.

To use Sass, first install node-sass:

$ npm install node-sass --save
$ # or
$ yarn add node-sass

Now you can rename src/App.css to src/App.scss and update src/App.js to import src/App.scss. This file and any other file will be automatically compiled if imported with the extension .scss or .sass.

To share variables between Sass files, you can use Sass imports. For example, src/App.scss and other component style files could include @import "./shared.scss"; with variable definitions.

This will allow you to do imports like

@import 'styles/_colors.scss'; // assuming a styles directory under src/
@import '~nprogress/nprogress'; // importing a css file from the nprogress node module

Note: You must prefix imports from node_modules with ~ as displayed above.

node-sass also supports the SASS_PATH variable.

To use imports relative to a path you specify, and from node_modules without adding the ~ prefix, you can add a .env file at the project root with the variable SASS_PATH=node_modules:src. To specify more directories you can add them to SASS_PATH separated by a : like path1:path2:path3.

If you set SASS_PATH=node_modules:src, this will allow you to do imports like

@import 'styles/colors'; // assuming a styles directory under src/, where _colors.scss partial file exists.
@import 'nprogress/nprogress'; // importing a css file from the nprogress node module

Note: For windows operating system, use below syntax

SASS_PATH=./node_modules;./src

Tip: You can opt into using this feature with CSS modules too!

Note: If you're using Flow, override the module.file_ext setting in your .flowconfig so it'll recognize .sass or .scss files. You will also need to include the module.file_ext default settings for .js, .jsx, .mjs and .json files.

[options]
module.file_ext=.js
module.file_ext=.jsx
module.file_ext=.mjs
module.file_ext=.json
module.file_ext=.sass
module.file_ext=.scss