https://www.macintosh-data-recovery.com/wp-content/themes/business/js/navigation.js

1/**
2 * navigation.js
3 *
4 * Handles toggling the navigation menu for small screens.
5 */
6( function() {
7	var container, button, menu;
8
9	container = document.getElementById( 'site-navigation' );
10	if ( ! container )
11		return;
12
13	button = container.getElementsByTagName( 'button' )[0];
14	if ( 'undefined' === typeof button )
15		return;
16
17	menu = container.getElementsByTagName( 'ul' )[0];
18
19	// Hide menu toggle button if menu is empty and return early.
20	if ( 'undefined' === typeof menu ) {
21		button.style.display = 'none';
22		return;
23	}
24
25	if ( -1 === menu.className.indexOf( 'nav-menu' ) )
26		menu.className += ' nav-menu';
27
28	button.onclick = function() {
29		if ( -1 !== container.className.indexOf( 'toggled' ) )
30			container.className = container.className.replace( ' toggled', '' );
31		else
32			container.className += ' toggled';
33	};
34} )();