Card survey format customization?

I am looking to be able to customize more on the card format (as opposed to the original layout with the full list of questions that has the advanced design tool). 

For example, I want to customize how the Thank you submission looks (ie, the font size, add a link, etc). 

We apologize for inconvenience. If I understand correctly, you were referring to the Card Form layout. Currently, unlike the Classic Form version, Card Forms does not have the form designer advance CSS editor option.

The Form Designer in Card Form have preset designed templates that can be used.

This also applies to customizing the Thank You page message of Card Form. If you need customized Thank You page in Card Forms, you will need to use your own custom Thank You page via the redirect to external URL option.

I hope this help. Please let us know if you need further assistance.