<!DOCTYPE html>
<html>
<head>
<style type="text/css">
#b {
 height: 20px;
 background-color: green;
}
#c {
 margin-top: 30px;
 margin-bottom: 40px;
 height: 0;
}
#d {
 height: 10px; width: 100px;
 background-color: red;
}
#e {
 height: 20px;
 background-color: green;
}
</style>
</head>
<body>
<div id="b"></div>
<div id="a">
 <div id="c">
  <div id="d"></div>
 </div>
</div>
<div id="e"></div>
</body>
</html>