webpack.common.js

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

module.exports = {
    entry: {
        app: path.resolve(__dirname, "src/App.jsx"),
        vendor: ['react', 'react-dom']
    },
    output: {
        path: path.resolve(__dirname, "dist"),
        filename: '[name].js',
        publicPath: '/dist/'
    },
    resolve: {
        extensions: ['.js', '.jsx', '.json']
    },
    module: {
        loaders: [
            {
                test: /.jsx?$/,
                exclude: /node_modules/,
                use: {
                    loader: 'babel-loader?cacheDirectory',
                    options: {
                        presets: ['env', 'react']
                    }
                }
            },{
                test: /\.scss$/,
                use: ExtractTextPlugin.extract({
                    fallback: 'style-loader',
                    use: ["css-loader","sass-loader"]
                })
            },{
                test: /\.css$/,
                use: ExtractTextPlugin.extract({
                    use: 'css-loader'
                })
            }
        ]
    },
    plugins: [
        new ExtractTextPlugin("styles.css")
    ]
};