Toggles the hamburger menu for the navbar list.
@private
@param {Boolean} show -
function toggleHamMenu(show) {
        if (!$nbmBtn) return;
        var fn = show ? 'addClass' : 'removeClass';
        $nbmBtn[fn]('toggled');
        $navOverlay[fn]('toggled'); // toggle overlay / backdrop
        $navbarMenu[fn]('toggled');
        // disable body scroll if menu is open
        helper.toggleBodyScroll(!show);

        if (show) {
            // scroll the contents of the responsive collapsed navbar menu to
            // top.
            $navbarMenu.scrollTop(0);
            // if showing responsive collapsed navbar menu, we'll close the
            // sidebar.
            if ($sidebarWrapper && $sidebarWrapper.length) {
                $wrapper.removeClass('toggled');
                $sidebarToggle.removeClass('toggled');
                // also hide the sidebar toggler, so user cannot re-open it
                // while navbar menu is shown. we use opacity instead of
                // display:none bec, it's used by a media query in sidebar.less
                // (the toggler is already hidden in small screens).
                $sidebarToggle.css('opacity', 0);
            }
        } else {
            // show sidebar toggler if responsive collapsed navbar menu is
            // closed.
            $sidebarToggle.css('opacity', 1);
        }
    }