Hi Brooke -
You may have to update at the question/field level. Click on the question/field you are trying to update and click on Customize:

Next, you'll want to click on Field:

Then you'll want to select the Font Color - this should update the font colors for all your shown selections as well as the color of the font in the text box:

If you've already tried this, and it still isn't working, the settings you may need to update may be part of the theme. You may already have custom colors set up as part of your Theme. If you are able to adjust it, the area that you are looking for (based on the screenshot that you provided) is Registration -> Fields -> Textbox Text.
Here are a couple of articles to reference, if you need more info:
https://support.cvent.com/s/communityarticle/Flex-Event-s-Widget-Applied-Style
https://support.cvent.com/s/communityarticle/Popular-Site-Designer-Terms
Hope this helps!
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Rebecca Yousif
Senior Administrator - Event Technology
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