Why Is My Popup Not Using My Theme Styles?
If you find that your popup is not using your theme styles as it should be, then look to your code to make sure your theme styles are applying globally.
This is usually the case when your theme doesn't have defaults. For example, let's say you have a CSS selector that looks like this:
This is going to apply the styles to lists that are only inside the content div. Which means any ul's you have in a popup will not inherit these styles.
If that is the case, the most effective solution is to make adjustments to the theme so that the same styles are applied globally, instead. That may be better asked of your theme author (if its not custom).
In this example, all it requires is changing your CSS selector from