first three menu working fine and others not working using
<p>I want to change menu background when someone reach that div/section in jquery three section working fine but after that my code is not working i don't know why, its sucking my blood since two days please solve my problem here <a href="http://staging.moosaconsulting.com/moosaconsulting/" rel="nofollow">its live site</a></p>

<p>and here is my jQuery code</p>

<pre><code>    var cul_home = $("#home").offset().top;
    var cul_culture = $("#culture").offset().top;
    var cul_work = $("#work").offset().top;
    var cul_services = $("#services").offset().top;
    var cul_careers = $("#careers").offset().top;
    var cul_contactus= $("#contactus").offset().top;
    var cul_locations= $("#locations").offset().top


    var $topscrol = $(window).scroll(function(){
    if ($topscrol.scrollTop() &gt; cul_home)
    {   
        $('#menu-item-1726').addClass('cltbck');//home
        $('#menu-item-1715').removeClass('cltbck');//culture
        $('#menu-item-1717').removeClass('worbck');//work
        $('#menu-item-1718').removeClass('serbck');//servicess
        $('#menu-item-1719').removeClass('cerbck');//careers
        $('#menu-item-1720').removeClass('conbck');//contactus
        $('#menu-item-1721').removeClass('locbck');//locations
    }
    else
    {
        $('#menu-item-1726').removeClass('cltbck');//home
    }
    if($topscrol.scrollTop() &gt; cul_culture)
    {
        $('#menu-item-1726').removeClass('cltbck');//home
        $('#menu-item-1715').addClass('cltbck');//culture
        $('#menu-item-1717').removeClass('worbck');//work
        $('#menu-item-1718').removeClass('serbck');//servicess
        $('#menu-item-1719').removeClass('cerbck');//careers
        $('#menu-item-1720').removeClass('conbck');//contactus
        $('#menu-item-1721').removeClass('locbck');//locations
    }
    else
    {
        $('#menu-item-1715').removeClass('cltbck');//home
    }

    if($topscrol.scrollTop() &gt; cul_work)
    {
        $('#menu-item-1726').removeClass('cltbck');//home
        $('#menu-item-1715').removeClass('cltbck');//culture
        $('#menu-item-1717').addClass('worbck');//work
        $('#menu-item-1718').removeClass('serbck');//servicess
        $('#menu-item-1719').removeClass('cerbck');//careers
        $('#menu-item-1720').removeClass('conbck');//contactus
        $('#menu-item-1721').removeClass('locbck');//locations

    }
    else
    {
        $('#menu-item-1717').removeClass('worbck');//home
    }
    if($topscrol.scrollTop() &gt; cul_services)
    {
        $('#menu-item-1726').removeClass('cltbck');//home
        $('#menu-item-1715').removeClass('cltbck');//culture
        $('#menu-item-1717').removeClass('worbck');//work
        $('#menu-item-1718').addClass('serbck');//servicess
        $('#menu-item-1719').removeClass('cerbck');//careers
        $('#menu-item-1720').removeClass('conbck');//contactus
        $('#menu-item-1721').removeClass('locbck');//locations

    }
    else
    {
        $('#menu-item-1718').removeClass('serbck');//home
    }
    if($topscrol.scrollTop() &gt; cul_careers)
    {
        $('#menu-item-1726').removeClass('cltbck');//home
        $('#menu-item-1715').removeClass('cltbck');//culture
        $('#menu-item-1717').removeClass('worbck');//work
        $('#menu-item-1718').removeClass('serbck');//servicess
        $('#menu-item-1719').addClass('cerbck');//careers
        $('#menu-item-1720').removeClass('conbck');//contactus
        $('#menu-item-1721').removeClass('locbck');//locations

    }
    else
    {
         $('#menu-item-1719').removeClass('cerbck');//home
    }

    if($topscrol.scrollTop() &gt; cul_contactus)
    {
        $('#menu-item-1726').removeClass('cltbck');//home
        $('#menu-item-1715').removeClass('cltbck');//culture
        $('#menu-item-1717').removeClass('worbck');//work
        $('#menu-item-1718').removeClass('serbck');//servicess
        $('#menu-item-1719').removeClass('cerbck');//careers
        $('#menu-item-1720').addClass('conbck');//contactus
        $('#menu-item-1721').removeClass('locbck');//locations

    }
    else
    {
        $('#menu-item-1720').removeClass('conbck');//contactus
    }

    if($topscrol.scrollTop() &gt; cul_locations)
    {
        $('#menu-item-1726').removeClass('cltbck');//home
        $('#menu-item-1715').removeClass('cltbck');//culture
        $('#menu-item-1717').removeClass('worbck');//work
        $('#menu-item-1718').removeClass('serbck');//servicess
        $('#menu-item-1719').removeClass('cerbck');//careers
        $('#menu-item-1720').removeClass('conbck');//contactus
        $('#menu-item-1721').addClass('locbck');//locations

    }
    else
    {
        $('#menu-item-1721').removeClass('locbck');//locations
    }

});
</code></pre>