I have an old pure HTML/CSS site that I want to clean up. I have two HTML pages that contain the same navigation bar. If I were using a framework like Django, I would extract that navigation bar HTML code into its own template (navigation.html) and then import that template using `{% include 'navigation.html' %}`. Is there a way to do the same thing without using a heavy framework? At the very least, I don't want to use any server-side scripts.