Prova cosi:
Codice PHP:
.first_class{
width:400px;
clear:both;
background:#666
}
.second_class{
width:100px;
float:left;
font-size:14px;
text-align:center
}
Codice PHP:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="it">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>test css netscape</title>
<link rel="stylesheet" type="text/css" href="style.css"/>
</head>
<body>
<div class="first_class">
<div class="second_class">
xxx</p>
</div>
</div>
</body>
</html>