nt.getElementById('layer'), 'layer');
        var frame = registerElem(document.getElementById('frame'), 'frame');
        var fbody = registerElem(frame.contentDocument.body, 'fbody');
      }
      window.addEventListener('load', init, false);
    </script>

    <style>
      iframe {
        position: absolute;
        top: 0px;
        left: 0px;
        width: 100px;
        height: 100px;
        background: blue;
      }
      div#layer {
        position: absolute;
        top: 50px;
        left: 5