title: division animate issue on jquery window scroll
body: <p>i want to animate division on window scroll, its only animate when scrollTop is greater than 200, and when i want to scroll back on  scrollTop greater > 500 it does nothing.</p>
  
  <pre><code>$(window).scroll(function(){
      var posFromTop = $(window).scrollTop();
  
      if(posFromTop &gt; 200){
          // if more than 200px from the top do something
          $('#banner').animate({'left': +300});}            
  
      if(posFromTop &gt; 500){
          // if more than 200px from the top do something
          $('#banner').animate('left': -300});}
      });
  });
  </code></pre>