newsupernova/app/code/Mageplaza/LayeredNavigation/view/frontend/templates/layer.phtml

<?php
/**
 * Mageplaza
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Mageplaza.com license that is
 * available through the world-wide-web at this URL:
 * https://www.mageplaza.com/LICENSE.txt
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade this extension to newer
 * version in the future.
 *
 * @category    Mageplaza
 * @package     Mageplaza_LayeredNavigation
 * @copyright   Copyright (c) 2017 Mageplaza (http://www.mageplaza.com/)
 * @license     https://www.mageplaza.com/LICENSE.txt
 */
?>

<div id="layered-filter-block-container" class="layered-filter-block-container">
    <?php echo $block->getChildHtml() ?>
</div>
<div id="ln_overlay" class="ln_overlay">
    <div class="loader">
        <img src="<?php echo $block->getViewFileUrl('images/loader-1.gif'); ?>" alt="Loading...">
    </div>
</div>