webpack.config.js

const path = require('path');

const HtmlWebpackPlugin = require('html-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');

module.exports = {
  entry: path.resolve(__dirname, 'src', 'index.js'),
  output: {
    filename: 'main.js',
    path: path.resolve(__dirname, 'dist'),
  },

  module: {
    rules: [
      {
        test: /\.(sa|sc|c)ss$/,
        use: [
          MiniCssExtractPlugin.loader,
          'css-loader',
          'sass-loader',
        ],
      },
      {
        test: /\.css$/i,
        use: [
          'style-loader',
          'css-loader',
        ]
      },
      {
        test: /\.js$/,
        exclude: /node_modules/,
        use: {
          loader: 'babel-loader',
          options: {
            presets: ['@babel/preset-env'],
          },
        },
      },
    ],
  },

  plugins: [
    new HtmlWebpackPlugin({
      filename: 'index.html',
      template: path.resolve(__dirname, 'public', 'index.html'),
    }),
    new MiniCssExtractPlugin({
      filename: 'styles.css',
    }),
  ]
};