title: What's wrong with this (animate) jquery code?
body: <pre><code>var object = $('#object');
  var start = $('#start');
  var normal = $('#object_normal');
  normal.hide();
  
  start.on('click', function(){
      object.animate({margin-bottom:'0px'}, 3000, function(){
                  normal.fadeIn(700) ;  
                     });
  });
  </code></pre>
  
  <p>can anyone explain why this code does not work? The variables and method outside the function do work. But when I add the function below, suddenly nothing happens. So there must be something wrong with the function.</p>