webpack.config.js

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

module.exports = {
    entry: {
        app: "./src/index.js"
    },
    output: {
        filename: "[name].js",
        path: path.resolve(__dirname, './dist/'),
        publicPath: "/dist/"
    },
    module : {
        rules: [
            {
            test: /\.js$/,
            exclude: '/node_modules/',
            loader: 'babel-loader'
        },
        {
            test: /\.css$/,
            use: [
                {
                    loader: MiniCssExtractPlugin.loader
                },
                {
                    loader: 'css-loader'
                },
                {
                    loader: 'postcss-loader',
                    options: {config: {path:'src/js/postcss.config.js'}}
                }
            ]
        }
    ]
    },
    devServer: {
        overlay: true
    },
    plugins: [
        new MiniCssExtractPlugin({
            filename: "[name].css"
        })
    ],
}