Как подключить стили из _header.scss в index.pug?

include pug/libs/_libs

doctype html
html(lang='ru')
  head
    meta(charset='UTF-8')
    meta(http-equiv='X-UA-Compatible' content='IE=edge')
    meta(name='viewport' content='width=device-width, initial-scale=1.0')
    title Document
    
  body
    header.header
      .header__container.flex
        a.header__logo(href='#')
          +image("logo")
          +image("burger")
        nav.header__nav
          a.header__menu(href='#')

Конфигурация webpack.config.js

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

let mode = "development";
if (process.env.NODE_ENV === "production") {
  mode = "production";
}
console.log(mode + " mode");

module.exports = {
  mode: mode,
  entry: {
    scripts: "./src/index.js",
  },
  output: {
    filename: "[name].[contenthash].js",
    assetModuleFilename: "assets/[hash][ext][query]",
    clean: true
  },
  devtool: "source-map",
  optimization: {
    splitChunks: {
      chunks: "all",
    },
  },
  plugins: [
    new MiniCssExtractPlugin({
      filename: "[name].[contenthash].css"
    }),
    new HtmlWebpackPlugin({
      template: "./src/index.pug"
  })],
  module: {
    rules: [
      {
        test: /\.html$/i,
        loader: "html-loader",
      },
      {
        test: /\.(sa|sc|c)ss$/,
        use: [
          (mode === "development") ? "style-loader" : MiniCssExtractPlugin.loader,
          "css-loader",
          {
            loader: "postcss-loader",
            options: {
              postcssOptions: {
                plugins: [
                  [
                    "postcss-preset-env",
                    {
                      // Options
                    },
                  ],
                ],
              },
            },
          },
          "sass-loader",
        ],
      },
      {
        test: /\.(png|svg|jpg|jpeg|gif)$/i,
        type: "asset/resource",
      },
      {
        test: /\.(woff|woff2|eot|ttf|otf)$/i,
        type: "asset/resource"
      },
      {
        test: /\.pug$/,
        loader: "pug-loader",
        exclude: /(node_modules|bower_components)/,
      },
      {
        test: /\.n?js$/,
        exclude: /node_modules/,
        use: {
          loader: "babel-loader",
          options: {
            presets: ["@babel/preset-env"]
          }
        }
      }
    ]
  },
}