{
  test: cssRegex,
  exclude: cssModuleRegex,
  use: getStyleLoaders({
    importLoaders: 1,
    sourceMap: isEnvProduction && shouldUseSourceMap,
    modules: {
      getLocalIdent: getCSSModuleLocalIdent,
    },
  }),
  sideEffects: true,
},
{
  test: cssModuleRegex,
  use: getStyleLoaders({
    importLoaders: 1,
    sourceMap: isEnvProduction && shouldUseSourceMap,
    modules: {
      getLocalIdent: getCSSModuleLocalIdent,
    },
  }),
},
{
  test: sassRegex,
  exclude: sassModuleRegex,
  use: getStyleLoaders({
      importLoaders: 3,
      sourceMap: isEnvProduction && shouldUseSourceMap,
      modules: {
        getLocalIdent: getCSSModuleLocalIdent,
      },
    },
    'sass-loader'
  ),
  sideEffects: true,
},
{
  test: sassModuleRegex,
  use: getStyleLoaders({
      importLoaders: 3,
      sourceMap: isEnvProduction && shouldUseSourceMap,
      modules: {
        getLocalIdent: getCSSModuleLocalIdent,
      },
    },
    'sass-loader'
  ),
},

declare module '*.css' {
  const classes: { readonly [key: string]: string };
  export default classes;
}

declare module '*.scss' {
  const content: {[className: string]: string};
  export default content;
}

//Header.tsx

import React from "react";
import styles from './Header.scss';

export default class Header extends React.Component {
    render() {
        return (
            <header className={styles.header}>
                Hello World!
            </header>
        )
    }
}

//Header.scss

.header {
  color: $white;
  background-color: $green;
  padding: 8px 10px;
  font-weight: 500;
  font-size: 16px;
}