webpack.config.js

const path = require('path');
const ExtractTextPlugin = require('extract-text-webpack-plugin');
module.exports = {
    entry: './src/index.js',
    output: {
        path: path.resolve(__dirname, './dist/'),
        filename: 'bundle.js'
    },
    module: {
        loaders: [
            {
                test: /\.js$/,
                loader: 'babel-loader',
                exclude: /node_modules/,
                query: {
                    presets: ['es2015']
                }
            },
            {
                test: /\.css$/,
                loader: ExtractTextPlugin.extract('css-loader')
            }
        ]
    },
    plugins: [
        new ExtractTextPlugin('style.css')
    ]
};