Ksheila - I'm not sure if you've worked out what went wrong yet? I've just shuffled my code around a bit and managed to get very similar to the example posted, although my text seems to be a slight bit smaller, but in the same proportions. I needed to change my .html file only.
If it helps you below is my new coding..
<DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
<title>First CSS Tutorial</title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">