( function() {
    'use strict';

    if ( 'querySelector' in document && 'addEventListener' in window ) {
        const hedi = document.querySelector( '.main-nav-2, .main-nav-3, .header, .header-4, .header-5, .header-6' );

        window.addEventListener( 'scroll', () => {
            if ( scrollY >= 50 ) {
                hedi.classList.add( 'sticky-header' );
            } else {
                hedi.classList.remove( 'sticky-header' );
            }
        });
    }
}) ();