webpack.config.js

const path = require('path');
const MiniCSSExtractPlugin = require('mini-css-extract-plugin');

module.exports = {
    entry: ['./src/index.js'],
    output: {
        path: path.join(__dirname, 'public', 'dist'),
        publicPath: '/dist/',
        filename: 'bundle.js'
    },
    plugins: [
        new MiniCSSExtractPlugin({
            filename: 'styles.css'
        })
    ],
    module: {
        rules: [
            {
                loader: 'babel-loader',
                test: /\.(js|jsx)$/,
                exclude: /node_modules/
            },
            {
                test: /\.s?css$/,
                use: [
                    MiniCSSExtractPlugin.loader,
                    'css-loader',
                    'sass-loader'
                ]
            },
            {
                test: /\.(gif|png|jpe?g|svg)$/i,
                use: [
                    {
                        loader: 'file-loader',
                        options: {
                            emitFile: false,
                            name: '[name].[ext]'
                        }
                    }
                ]
            }
        ]
    },
    devServer: {
        contentBase: path.join(__dirname, 'public'),
        historyApiFallback: true,
        publicPath: '/dist/',
        port: '4002'
    }
};