reading css?

lets say I have the style

 

body {

    color: red;

}

 

If I created a web-browser how would I read this? How would I not read
comments, and only read the data which I want?

 

Is there any guidelines how I should read it? Should I convert it into an
xml style document, then parse that?  If so, how would I convert it into the
xml format?