offset half window height
<p>I'm trying to write 50% of body height as the addition: <code>.scrollTop() + 50%}</code> rather than <code>.scrollTop() + 200}</code> So when the mouse leaves the <code>#tail</code> div snaps back to half the window height.</p>

<pre><code>    .bind('mouseleave', function(){
     $('#wrapper').unbind('mousemove');

          $('#tail').animate({top:$('body').scrollTop() + 50%},300)   
});
</code></pre>

<p>Whats the correct way to add a percent value? </p>

<p>Thanks</p>
