A Class Selector Rule

Look, this is really, really, really important.

<HTML>

<HEAD>
	<STYLE TYPE="text/css">
		B.extra { font-style: italic; font-size: 18pt; } 
		.huge {font-size: 42pt; }
	</STYLE>
</HEAD>

<BODY>

Look, this is <B>really</B>, <B CLASS="extra">really</B>, <BIG CLASS="huge">really</BIG> important.

</BODY></HTML>