webpack.config.js

const path = require('path');
const ExtractTextPlugin = require('extract-text-webpack-plugin');

module.exports = {
  context: __dirname,
  mode: process.env.NODE_ENV || 'production',
  entry: {
    app: [
      './app/js/index.js',
      './app/styles/styles.css'
    ]
  },
  output: {
    filename: '[name].js',
    path: path.resolve(__dirname, 'dist')
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: [
              ["env", {
                "targets": {
                  "browsers": ["last 2 versions", "safari >= 7"]
                }
              }]
            ]
          }
        },
        exclude: path.join(__dirname, 'node_modules')
      },
      {
        test: /\.css$/,
        use: ExtractTextPlugin.extract({
          fallback: 'style-loader',
          use: [
            {
              loader: 'css-loader',
              options: {
                importLoaders: 1
              }
            },
            {
              loader: 'postcss-loader',
              options: {
                ident: 'postcss',
                // parser: scss,
                plugins: [
                  require('postcss-import')({ root: path.join(__dirname, 'app/styles'), }),
                  require('postcss-cssnext')({ browsers: [ 'last 2 versions' ] }),
                  require('postcss-nesting')(),
                  require('postcss-inline-svg')(),
                  require('cssnano')()
                ]
              }
            }
          ]
        })
      },
      {
        test: /\.(png|jpg|jpeg|gif|svg|woff|woff2|ttf|eot)$/,
        loader: 'file-loader'
      }
    ]
  },
  plugins: [
    new ExtractTextPlugin('[name].css')
  ],
  resolve: {
    alias: {
      // add aliases
    }
  }
};