webpack.config.js

const path = require('path');

const SRC_DIR = path.join(__dirname, '/client/src');
const DIST_DIR = path.join(__dirname, '/client/dist');

module.exports = {
  mode: 'development',
  entry: `${SRC_DIR}/index.jsx`,
  output: {
    filename: 'bundle.js',
    path: DIST_DIR,
  },
  module: {
    rules: [
      {
        test: /\.jsx?/,
        include: SRC_DIR,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['@babel/preset-env', '@babel/preset-react'],
          },
        },
      },
      {
        test: /\.css$/i,
        exclude: /node_modules/,
        use: ['style-loader', 'css-loader'],
      },
      {
        test: /\.s[ac]ss$/i,
        use: [
          // Creates `style` nodes from JS strings
          'style-loader',
          // Translates CSS into CommonJS
          'css-loader',
          // Compiles Sass to CSS
          'sass-loader',
        ],
      },
    ],
  },
};