function nav(){

    var pageName = document.URL.substring(document.URL.lastIndexOf("/")+1, document.URL.lastIndexOf("."));
    if(pageName == ".uk/" || pageName == ".com/" || pageName == "/" || pageName == ""){
        pageName = "index";
    }
    
    var allLists = document.getElementsByTagName("ul");
    var i;
    for(i=0; i<allLists.length; i++)
    {
        if(allLists[i].className == "trip_down_project_main_navigation_container")
        {
            var headerLinks = allLists[i].getElementsByTagName("a");
            var j;
            for(j=0; j<headerLinks.length; j++)
            {
                if(headerLinks[j].href.substring(headerLinks[j].href.lastIndexOf("/")+1, headerLinks[j].href.lastIndexOf(".")) == pageName)
                {
                    headerLinks[j].className = "on";
                    break;
                }
                else 
                {
                    headerLinks[j].className = "off";
                }
            }    
        }
    }    
}