( function() {

    container = document.getElementById( 'site-header' );
	if ( ! container ) {
		return;
	}

	button = container.getElementsByTagName( 'button' )[0];
	if ( 'undefined' === typeof button ) {
		return;
	}

	menu = container.getElementsByTagName( 'ul' )[0];

	// Hide menu toggle button if menu is empty and return early.
	if ( 'undefined' === typeof menu ) {
		button.style.display = 'none';
		return;
	}

}) ();