NOTE: You probably don't need this plugin!

Gatsby works with CSS Modules by default, no need for extra plugins. You should only use this if you already know what babel-plugin-react-css-modules is and want to enable it for your project.

gatsby-plugin-react-css-modules

Transforms styleName to className using compile time CSS module resolution. See the babel-plugin-react-css-modules README for details.

Install

npm install gatsby-plugin-react-css-modules

How to use

// In your gatsby-config.js
plugins: [
  {
    resolve: `gatsby-plugin-react-css-modules`,
    options: {
      // *.css files are included by default.
      // To support another syntax (e.g. SCSS),
      // add `postcss-scss` to your project's devDependencies
      // and add the following option here:
      filetypes: {
        ".scss": { syntax: `postcss-scss` },
      },

      // Exclude global styles from the plugin using a RegExp:
      exclude: `\/global\/`,
      // For all the options check babel-plugin-react-css-modules README link provided above
    },
  },
]

Files must be named using the pattern filename.module.css for Gatsby to treat them as CSS modules. You can change this behavior using a custom webpack config https://www.gatsbyjs.com/docs/add-custom-webpack-config/