var toggleMenu = function()
{
    var nav = document.getElementById('nav');
    var as = nav.getElementsByTagName('a');
    for (var i=0; i<as.length; i++) {
        as[i].onmouseover = function()
        {
            spans = this.getElementsByTagName('span');
            span = spans[0];
            span.style.backgroundPosition = "0 0";
            span.style.backgroundColor = "#10376a";
        }
        as[i].onmouseout = function()
        {
            spans = this.getElementsByTagName('span');
            span = spans[0];
            span.style.backgroundPosition = "0 -66px";
            span.style.backgroundColor = "#c4d338";
        }
    }
}
if (window.attachEvent) {
    window.attachEvent("onload", toggleMenu);
} else if (window.addEventListener) {
    window.addEventListener("load", toggleMenu, false);
}

function popup(href)
 {
      window.open(href, 'imgWin', 'width=400,height=400');
}