Simple Webpack.config.js

const path = require('path');
module.exports = {
  devtool: 'cheap-module-eval-source-map',
  entry: path.join(__dirname, './src/index.js'),
  output: {
    path: path.join(__dirname, './dist'),
    filename: 'main.js'
  },
  devServer: {
    publicPath: './dist/'
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        exclude: /node_modules/,
        loader: 'babel-loader'
      },
      {
        test: /\.css$/,
        use: ['style-loader', 'css-loader']
      }
    ]
  }
};