// Custom Script 
function custom_script() {
    wp_enqueue_script( 'magnific-popup-js', 'https://cdnjs.cloudflare.com/ajax/libs/magnific-popup.js/1.2.0/jquery.magnific-popup.min.js', null, null, true );
    wp_enqueue_style('magnific-popup-css', 'https://cdnjs.cloudflare.com/ajax/libs/magnific-popup.js/1.2.0/magnific-popup.min.css');
}
add_action('wp_enqueue_scripts','custom_script');