$.extend({
  getUrlVars: function(){
    var vars = [], hash;
    var hashes = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');
    for(var i = 0; i < hashes.length; i++)
    {
      hash = hashes[i].split('=');
      vars.push(hash[0]);
      vars[hash[0]] = hash[1];
    }
    return vars;
  },
  getUrlVar: function(name){
    return $.getUrlVars()[name];
  }
});

$(function() {
	var pid = "?p=" + $.getUrlVar('p');
	var $top = $('#nav li.top > a[href*=' + pid + ']:last');
	if ($top.length > 0) {
		$top.css('background-position', '0 54px');
	}
	else {
		$('#nav a[href*=' + pid + ']:last').parents('li.top:eq(0)').children('a').css('background-position', '0 54px');
	}
});