<!DOCTYPE html>
<html>
<head>
<style type="text/css">
#bar1 {
 height: 20px;
 background-color: green;
 margin-bottom: 10px;
}
#none {
 display: none;
 height: 20px;
 background-color: red;
 margin-top: 30px;
 margin-bottom: 40px;
}
#bar2 {
 height: 20px;
 background-color: blue;
 margin-top: 20px;
}
</style>
</head>
<body>
<div id="bar1"></div>
<div id="none"></div>
<div id="bar2"></div>
</body>
</html>