https://blog.tomayac.com/2019/09/21/prefers-color-scheme-in-svg-favicons-for-dark-mode-icons/
prefers-color-scheme in SVG favicons for dark mode icons
Nov 20, 2019 - The personal blog of Thomas Steiner
prefers color schemedark mode
https://www.caniemail.com/features/css-at-media-prefers-color-scheme/
Can I email… @media (prefers-color-scheme)
Supported in Apple Mail. Partially supported in Outlook. Not supported in Gmail, Yahoo! Mail.
prefers color schememedia