function openLayer(url,w,h)
{

    var layer_width = 700;
    //an den anfang der Seite springen
    self.scrollTo(0, 0);

    hgesamt = document.getElementById('page_all').offsetHeight;

    var arrayPageSize = document.viewport.getDimensions();
    $('overlay').setStyle({ width: arrayPageSize.width + 'px', height: hgesamt + 'px' });


    new Effect.Appear($('overlay'), { duration: 0.2, from: 0.0, to: 0.9 });

    document.getElementById("layer_content").innerHTML = '<iframe src="' + url + '" width="'+w+'" height="'+h+'" scrolling="hidden" border="0"></iframe>';

    $('layer').setStyle({

        left: parseInt((document.viewport.getWidth() - layer_width) / 2) + 'px',
        top: parseInt(20) + 'px'
    });
    new Effect.Appear($('layer'), { duration: 0.2 });

}

function closeLayer()
{
   new Effect.Fade($('layer'), { duration: 0.2});
   new Effect.Fade($('overlay'), { duration: 0.2, from: 0.9, to: 0.0 });
   document.getElementById("layer_content").innerHTML = '';
 }