<html>
<head>
<style>
.middle {
  background-color:green;
  -moz-box-flex: 1;
  -webkit-box-flex: 1;
  box-flex: 1;
  border: 10px solid olive;
}

html {
  background-color: white;
  height: 100%;
}

body {
  height: 100%;
  margin: 0px;
}

div.outer {
  display: -moz-box;
  display: -webkit-box;
  display: box;
  -moz-box-orient: vertical;
  -webkit-box-orient: vertical;
  box-orient: vertical;
  height: 100%;
  width: 100%;
}
</style>
</head>
<body>
<div class="outer">
<div>
This header should remain at the top of the browser window as you resize it.  It
can wrap to multiple lines.  The center should be filled with an olive-bordered
green box.  It should start beneath the header, end above the footer, and fill the width of the
browser window.
</div>
<!--<div class="middle"></div>-->
<iframe class="middle" style="display: block; width:99%" src="about:blank"></iframe>
<div>
This footer should remain at the bottom of the browser window.  It
can wrap to multiple lines if necessary.
</div>
</div>
</body>
</html>