How to change the font color in order confirmation email?

We just launched a Magento 2.4, and this is the first Magento site where I’ve had access to the backend, so I’m just starting to learn “the lay of the land” so to speak.

I want to change the font color of the order confirmation email from gray to black. There isn’t any option in Magento admin (Marketing>Email templates) to change the font or color.

When I view source of the order confirmation preview, it shows 22 different stylesheets.

Any suggestions on how to proceed? Thank you in advance!