Fatal error: Uncaught Error: Call to undefined function wp_enqueue_style() in /home/k1818436/public_html/wp-content/plugins/pdf-viewer-for-wordpress/admin/upload_file.php:5 Stack trace: #0 {main} thrown in /home/k1818436/public_html/wp-content/plugins/pdf-viewer-for-wordpress/admin/upload_file.php on line 5