transform:rotate(30deg)
<!DOCTYPE html>
<html>
<head>
<title>css3</title>
<meta charset="utf-8">
<style type="text/css">
.box{
width: 100px;
height: 100px;
border: 1px solid #ccc;
background: yellow;
transform: rotate(30deg);
margin: 50px auto;
}
</style>
</head>
<body>
<div class="box"></div>
</body>
</html>
