Have you asked it to use different fonts ?

You might want to look at using codex or opencode with ChatGPT.

It’s not immediately clear if you’re just trying to get a better user experience for yourself or you’re trying to get the llm to output it with some style.

What prompt(s) are you giving it?

Chatgpt generates markdown output by default, which supports titles, bold text ... Etc but doesn't support colored text. I would try to ask to generate html. It would not be supported by its client, you would have to open the file in a browser.