minetest-bower/assets/AppAsset.php

<?php

namespace app\assets;

use yii\web\AssetBundle;

class AppAsset extends AssetBundle
{
    public $sourcePath = '@app/assets/web';
    public $css = [
        'css/site.css',
    ];
    public $depends = [
        'yii\web\YiiAsset',
        'yii\bootstrap\BootstrapAsset',
    ];
}