Change Font Color

One question, how can I change the font color of one class?

I have the following:

$p = new PCompositeNode();
$r = new RCompositeNode();
$p->addNode($r);
$r->addTextStyle(new BoldStyleNode());
$r->addTextStyle(new FontSizeStyleNode(10));

It's bold and size 10, but i want to be some color (example, red)

Thanks,