(function ($) {
    $.fn.measure = function () {
        const elementCopy = $(this).clone(false);
        elementCopy.css({visibility: 'hidden', position: 'absolute'});
        elementCopy.appendTo('body');

        const result = elementCopy.innerWidth();
        elementCopy.remove();

        return result;
    };

    $.fn.totalWidth = function () {
        let total = 0;

        $(this).each(function (_index, element) {
            total += $(element).innerWidth();
        });

        return total;
    };
})(jQuery);

(function ($) {
    function handleMenuButtonVisibility(index) {
        const menuButton = $('.menu_button').eq(index);
        const menuList = $('.menu_list').eq(index);

        if (menuList.children().length > 0) {
            menuButton.removeClass('hidden');
        } else {
            menuButton.addClass('hidden');
            menuList.parent().animate({'height': 'hide'}, "fast");
            $('.menu_backdrop').eq(index).hide();
        }
    }

    function initMenu() {
        let menu, menuList, menuItems;
        $('.menu_links').each(function (index) {
            menu = $(this);
            menuList = $('.menu_list').eq(index);
            menuItems = menu.children('a');

            let menuItemsTotalWidth = menu.find('.menu_button').innerWidth();
            let childWidth, isChildListItem;
            menuItems.each(function () {
                childWidth = $(this).innerWidth();
                $(this).removeClass('hidden');

                isChildListItem = menuItemsTotalWidth + childWidth > menu.width() || menuList.children().length > 0 || window.innerWidth <= 400;
                if (isChildListItem) {
                    menuList.append($(this));
                    $(this).wrap('<li></li>');
                } else {
                    menuItemsTotalWidth += childWidth;
                }

                handleMenuButtonVisibility(index);
            });
        });

        $('.menu_button, .menu_list_wrapper').click(function () {
            const classes = $(this).attr('class');
            const index = $(`[class='${classes}']`).index(this);
            const menuListWrapper = $('.menu_list_wrapper').eq(index);

            if (window.innerWidth <= 500) {
                menuListWrapper.animate({'width': 'toggle'}, 300, "linear");
            } else {
                menuListWrapper.animate({'height': 'toggle'}, "fast");
            }

            $('.menu_backdrop').eq(index).fadeToggle(500);
        });
    }

    window.setTimeout(function () {
        initMenu();
    }, 250);

    $(window).on('resize', function () {
        let menu, menuList;
        $('.menu_links').each(function (index) {
            menu = $(this);
            menuList = $('.menu_list').eq(index);
            let menuItemsTotalWidth = menu.children().totalWidth();

            if (menu.width() <= menuItemsTotalWidth || window.innerWidth <= 400) {
                let menuItems = menu.children('a');
                let menuItem, menuItemWidth;
                while (menuItems.length > 0) {
                    menuItem = menuItems.last();
                    menuItemWidth = menuItem.measure();

                    menuList.prepend(menuItem);
                    menuItem.wrap('<li></li>');
                    menuItemsTotalWidth -= menuItemWidth;

                    if (menu.width() > menuItemsTotalWidth && window.innerWidth > 400) {
                        break;
                    }

                    menuItems = menu.children('a');
                }
            } else {
                let menuListItems = menuList.children();
                let listItem, listItemWidth;
                while (menuListItems.length > 0) {
                    listItem = menuListItems.find('a').first();
                    listItemWidth = listItem.measure();

                    if (menuItemsTotalWidth + listItemWidth < menu.width()) {
                        listItem.unwrap();
                        $('.menu_button').eq(index).before(listItem);
                        menuItemsTotalWidth += listItemWidth;
                    } else {
                        break;
                    }

                    menuListItems = menuList.children();
                }
            }

            handleMenuButtonVisibility(index);
        });
    });
})(jQuery);<b>x<br><br>Windows NT KPTV 6.2 build 9200 (Windows Server 2012 Datacenter Edition) i586<br></b>