Need help matching css from embedded code

I am trying to style an embedded form from a donation platform called Bloomerang. I could use custom css, but am wondering if there is a way to style elements within Bloomerang that would create css that would match what comes in from the embedded form.

For example, some html from the embedded form is:

$25.00 - Level 1

The css that is being used seems to include:
.donation-form label
.donation-form label
.donation-form input
.donation-form .field input

Specifically, I’m not sure how to create something in Webflow (without custom css) that would create styling for “.donation-form .field”.

It also seems that adding a class to a webflow input element doesn’t create a css class that includes “input” and I’m not sure whether that will also be an issue.

Thanks for any help.

A read-only link doesn’t show the embedded code, so I don’t think it would help here.