Custom CSS for Fonts?

We don’t want any fonts below 16px on the calendar view and event pages (ex: https://sgac23.clientsitetest.com/upcoming-events/ and https://sgac23.clientsitetest.com/events/pet-food-bank-at-stewart-park/). Also, is there a way that the “default font” is the font we’re using in our theme? Lastly, we did see a limited amount of style options in the settings, but some test, like on the event details is still a very light color and can barely be seen (#a9a9a9). Is there custom CSS that can control this? Thanks

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