Problème d'installation bootstrap in webpack sous symfony 5

Bonjour,

J'ai installé un webpack dans mon projet symfony 5 mais quand je tape la commande $npm run build, j'obtients l'erreur ci-dessous:

Failed to compile.

Module parse failed: Unexpected character '@' (1:0)
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
> @import "custom";
| @import "~bootstrap/scss/bootstrap";

Mon webpack.config.js

const Encore = require('@symfony/webpack-encore');

// Manually configure the runtime environment if not already configured yet by the "encore" command.
// It's useful when you use tools that rely on webpack.config.js file.
if (!Encore.isRuntimeEnvironmentConfigured()) {
    Encore.configureRuntimeEnvironment(process.env.NODE_ENV || 'dev');
}

Encore
    // directory where compiled assets will be stored
    .setOutputPath('public/build/')
    // public path used by the web server to access the output path
    .setPublicPath('/build')
    // only needed for CDN's or sub-directory deploy
    //.setManifestKeyPrefix('build/')

    /*
     * ENTRY CONFIG
     *
     * Each entry will result in one JavaScript file (e.g. app.js)
     * and one CSS file (e.g. app.css) if your JavaScript imports CSS.
     */
    .addEntry('app', './assets/app.js')

    // enables the Symfony UX Stimulus bridge (used in assets/bootstrap.js)
    .enableStimulusBridge('./assets/controllers.json')

    // When enabled, Webpack "splits" your files into smaller pieces for greater optimization.
    .splitEntryChunks()

    // will require an extra script tag for runtime.js
    // but, you probably want this, unless you're building a single-page app
    .enableSingleRuntimeChunk()

    /*
     * FEATURE CONFIG
     *
     * Enable & configure other features below. For a full
     * list of features, see:
     * https://symfony.com/doc/current/frontend.html#adding-more-features
     */
    .cleanupOutputBeforeBuild()
    .enableBuildNotifications()
    .enableSourceMaps(!Encore.isProduction())
    // enables hashed filenames (e.g. app.abc123.css)
    .enableVersioning(Encore.isProduction())

    .configureBabel((config) => {
        config.plugins.push('@babel/plugin-proposal-class-properties');
    })

    // enables @babel/preset-env polyfills
    .configureBabelPresetEnv((config) => {
        config.useBuiltIns = 'usage';
        config.corejs = 3;
    })

    // enables Sass/SCSS support
    .enableSassLoader()

    // uncomment if you use TypeScript
    //.enableTypeScriptLoader()

    // uncomment if you use React
    //.enableReactPreset()

    // uncomment to get integrity="..." attributes on your script & link tags
    // requires WebpackEncoreBundle 1.4 or higher
    //.enableIntegrityHashes(Encore.isProduction())

    // uncomment if you're having problems with a jQuery plugin
    //.autoProvidejQuery()
;

module.exports = Encore.getWebpackConfig();

Mon package.json

{
    "devDependencies": {
        "@symfony/stimulus-bridge": "^2.0.0",
        "@symfony/webpack-encore": "^1.0.0",
        "core-js": "^3.0.0",
        "css-loader": "^5.2.4",
        "jquery": "^3.6.0",
        "node-sass": "^5.0.0",
        "popper.js": "^1.16.1",
        "regenerator-runtime": "^0.13.2",
        "sass-loader": "^9.0.1",
        "stimulus": "^2.0.0",
        "webpack": "^5.36.2",
        "webpack-notifier": "^1.6.0"
    },
    "license": "UNLICENSED",
    "private": true,
    "scripts": {
        "dev-server": "encore dev-server",
        "dev": "encore dev",
        "watch": "encore dev --watch",
        "build": "encore production --progress"
    },
    "dependencies": {
        "@popperjs/core": "^2.9.2",
        "autoprefixer": "^10.2.5",
        "bootstrap": "^5.0.0-beta3",
        "postcss-loader": "^5.2.0"
    }
}

Mon app.js

/*
 * Welcome to your app's main JavaScript file!
 *
 * We recommend including the built version of this JavaScript file
 * (and its CSS file) in your base layout (base.html.twig).
 */

// any CSS you import will output into a single css file (app.css in this case)
import './styles/custom.scss';
import './styles/app.scss';

// const $ = require('jquery');
import { Tooltip, Toast, Popover } from 'bootstrap';
// import 'bootstrap/dist/js/bootstrap.min.js';
// import 'bootstrap/dist/css/bootstrap.min.css';

// start the Stimulus application
import './bootstrap';

Mon app.css

@import "custom";
@import "~bootstrap/scss/bootstrap";

Mon custom.css

$body-bg: #000;
$body-color: #111;

J'ai besoin de votre aide mes amis si vous pouvez le faire !!!