Laravel не видит стили из layout_rules

const 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 the application as well as bundling up all the JS files.
 |
 */

mix
    .setPublicPath('public/build')
    .setResourceRoot('/build/')
    .js('resources/js/app.js', 'js')
    .sass('resources/sass/app.scss', 'css')        

@import 'layouts';

@import 'layout_rules/header';

header {
    display: flex;
    align-items: center;
    width: 100%;
    height: 75px;
}