add_action(
    'wp_enqueue_scripts', 
    function() {
         if ( ! is_page() ...... ) {
             return;
         }
         wp_enqueue_style( slug, url, requirements[], version );
    }
);

                $this->parent->admin_notices[] = array(
                    'type'    => 'error',
                    'msg'     => '<strong>' . __( 'File Permission Issues', 'redux-framework' ) . '</strong><br/>' . sprintf( __( 'We were unable to modify required files. Please check your permissions, or modify your wp-config.php file to contain your FTP login credentials as <a href="%s" target="_blank">outlined here</a>.', 'redux-framework' ), 'https://codex.wordpress.org/Editing_wp-config.php#WordPress_Upgrade_Constants' ),
                    'id'      => 'redux-wp-login',
                    'dismiss' => false,
                );