Outlook dark mode keeps inverting our logo background

We ship B2B newsletters with a white header bar and a full-color logo on #FFFFFF. In Outlook desktop dark mode, the header flips to a dark gray and our white logo disappears. We tried wrapping the logo in a table with explicit bgcolor="#FFFFFF" but Outlook still recolors it on some builds. Has anyone found a reliable pattern that survives both light and dark mode without serving separate templates?

Outlook applies its own color transforms regardless of how clean your CSS is. Two things helped our retail clients: first, add the MSO meta tag for dark mode support and declare data-ogsc/data-ogsb attributes on key containers. Second, ship a PNG logo with a subtle non-white matte (light gray #F4F4F4) so inversion does not erase the mark. It is not elegant, but it beats an invisible logo. Full write-up is in the email-client-css guide on this site.

Dark mode issues will not hurt deliverability, but they will hurt trust when the brand looks broken. We run Litmus previews on every template change and tag Outlook dark mode as a separate checkpoint. If the logo fails there, we do not schedule the send. Worth the ten minutes.

Solo founder perspective: I stopped fighting perfect parity and moved the logo onto a colored brand bar (#1A3A5C) with a white knock-out version of the mark. Dark mode inversion then keeps enough contrast either way. Not what the brand book originally specified, but it renders consistently in Gmail iOS, Apple Mail, and Outlook desktop in our last test batch.

Update: combining Elena's PNG-on-light-gray trick with a brand-color header row fixed 90% of cases. Still seeing one odd build on Outlook 2021 where linked images get recolored. We are testing VML fallback next. Thanks for the pointers.