main.less

/* File laramix/main.less */

@import '../node_modules/bootstrap/dist/css/bootstrap.css';
@import '../node_modules/admin-lte/dist/css/AdminLTE.css';
@import '../node_modules/admin-lte/dist/css/skins/_all-skins.css';
@import '../node_modules/font-awesome/css/font-awesome.css';
@import '../node_modules/admin-lte/plugins/iCheck/all.css';
@import 'css/app.less';

webpack.mix.js

let mix = require('laravel-mix');

/*
 |--------------------------------------------------------------------------
 | Mix Asset Management
 |--------------------------------------------------------------------------
 |
 | Mix provides a clean, fluent API for defining some Webpack build steps
 | for your Laravel application. By default, we are compiling the Sass
 | file for your application, as well as bundling up your JS files.
 |
 */
mix.setPublicPath('web')
    .options({processCssUrls: false})
    .disableNotifications();

mix.scripts([
    'node_modules/jquery/dist/jquery.js',
    'laramix/js/sidebar-adminlte.js',
    'vendor/yiisoft/yii2/assets/yii.js',
    
    'node_modules/bootstrap/dist/js/bootstrap.js',
    'node_modules/admin-lte/dist/js/adminlte.js',
    'node_modules/admin-lte/plugins/iCheck/icheck.js',
], 'web/mix/js/static-main.js');

mix.less('laramix/main.less', 'web/mix/css/static-main.css');

mix.copy('node_modules/bootstrap/dist/fonts/', 'web/mix/fonts/')
    .copy('node_modules/font-awesome/fonts/', 'web/mix/fonts/')
    .copy('node_modules/admin-lte/plugins/iCheck/', 'web/mix/css/');

mix.sourceMaps();