I'd like to differentiate clearly between previous sections and the current section, so players can more easily keep track of their place in the text. For instance, when the player goes to a new section, the text in the previous section could turn gray. I'd rather not clear the screen entirely, because it's nice to be able to scroll back and see what you've done previously, but I do think players sometimes have difficulty keeping track of where the current active section begins (since the horizontal rule could indicate either a new section, or a new passage).

Is there a relatively simple way to apply a different style to old sections?