function get_para() {
  var url = window.location.href;
  var val = url.replace(/^.*\?/,'');
  return val;
}

function messe_popup(id) {
  var ah = screen.availHeight;
  var aw = screen.availWidth;
  var wh = 500;
  var ww = 520;
  var ll = (ah - wh) / 2;
  var rr = (aw - ww) / 2;
  var loc = '/products.html?'+id;
  window.open(loc,'PRODUCTS','scrollbars=0,toolbars=0,width='+ww+',height='+wh+',left='+rr+',top='+ll+'screenX='+rr+',screenY='+ll);
}