<html>
<head>
<style>
  body{height:100%; margin:0;}
  .sidebar{height:100%; display: inline-block; background: red; width:300px;vertical-align:top;}
.content{width: calc(100%  - 300px); display:inline-block; background:#eee; height:100%;}
footer{height:100px; background: #aaa;}
</style>
</head>
<body>
 <div class="sidebar">sidebar</div><div class='content'>content</div>
<footer>footer</footer>
</body>
</html>$(form).submit(function(){
 var that = $(this);
  var url = that .attr('action');
  var method = that .attr('method');
  $.ajax({
   type: method,
   url: url,
   data: that .serialize(),
   beforesend: function(){
   that.attr('disabled','true');
   },
  success: function(){
  },
  complete: function(){
   that.attr('disabled','false');
  }
  });