$(function() {
    var active = $('.header .menu .active'),
        activeArrow = $('.header .active-status'),
        menuItems = $('.header .menu li'),
        lastItem = $('.header .menu li:last-child');
    if (active.length) {
        var offset = active.position();
        var width = active.width();
        activeArrow.css('left', (offset.left - 10) + (width / 2));
    }
    else {
        var offset = lastItem.position();
        activeArrow.css('left', offset.left - 10);
    }
});