Upfront Overrides Custom CSS


This is just a simple question. Why would Upfront override my custom CSS for some HTML I put in? (My code is the CSS and HTML placed into a Code Block Element. Completely custom section)

I have paragraph styles and character styles and my fonts were overridden by the Theme Settings/Type Settings. Specifically, the <a href> was being forced to the font: Lato, because that is what was selected in the Type Settings. But I had paragraph styles and character styles in place to change the font which were not being accepted. I even put into the style sheet:

a {
font-family: Arial, sans-serif;

And that did not work. So I changed the type settings and it did make the change I wanted, but only because I wanted Arial. My concern is that while working right now, that any other future elements that are custom, I will not be able to use the font that I want due to Upfront overriding my custom CSS.

I am just looking for general thoughts on how I can force my fonts through and have them be top priority instead of what Upfront is pushing through the type settings.

Thanks so much!