Card Form: How to change colors of the "Save and Continue" icon?

I just added the Save & Continue option to my card forms. The icon is not very obvious, using our custom Theme. Can you tell me which setting(s) in Themes this icon follows? I changed Button Text and some others, with no success. Thank you!

I don't see any option to change the color of the save icon in the form designer so let me escalate this to our developers. Once this is implemented, we'll inform you here.