Coming Oct 1
The new html email formatting includes graphic elements to draw attention to your messages.
Plus subscribers can specify their desired text and colors for the header and footer background and font.
Premium subscribers also have the option of adding a logo or banner image to their emails.
Go to: Admin > Site Settings > Communications > Customize Email Look and Feel
To obtain color codes matching an existing image, use a free online tool, such as this one: https://html-color-codes.info/colors-from-image/