Untitled

<html>
<head>
<title> title </title>
<body>
<div id="main">
<div id="content2"> this is content2</div>
<div id="content3"> this is content3</div>
</div>
</body>
</html>

<html>
<head>
<title> title </title>
<body>
<div id="main">
<div id="content1"> this is content1</div>
<a href="#"> get content</a>
</div>
</body>
</html>

<html>
<head>
<title> title </title>
<body>
<div id="main">
<div id="content1"> this is content1</div>
<div>this is content2</div>
<div>this is content3</div>
</div>
</body>
</html>