CSS property · data last changed 10 Nov 2026
light-dark in email clients
Works in 3 of 21. Not supported in Gmail, Gmail Android, Gmail iOS and 8 more. Partial in Samsung Mail, HEY Mail and Proton Mail. Untested in Outlook Android, Yahoo Mail Android, Fastmail and 1 more.
Your reader in Outlook Classic sees the email without light-dark, even if it looks right where you tested it.
caniemail (MIT) via @emailens/engine 0.18.22
What to do instead in Outlook Classic
There is no drop-in fix for light-dark in Outlook Classic. Design so the email still reads without it.
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light-dark is not among the 24 features we have screenshotted on real installs. The ones we have →
All 21 clients, problems first
| Client | Support |
|---|---|
| Gmail | Not supported |
| Gmail Android | Not supported |
| Gmail iOS | Not supported |
| Outlook 365 | Not supported |
| Outlook (New) | Not supported |
| Outlook Classic | Not supported |
| Outlook iOS | Not supported |
| Outlook for Mac | Not supported |
| Yahoo Mail | Not supported |
| Yahoo Mail iOS | Not supported |
| AOL Mail | Not supported |
| Samsung Mail | Partial See caveat 2 |
| HEY Mail | Partial See caveat 3 |
| Proton Mail | Partial See caveat 3 |
| Outlook Android | Untested |
| Yahoo Mail Android | Untested |
| Fastmail | Untested |
| Superhuman | Untested |
| Apple Mail | Works See caveat 1 |
| Apple Mail iOS | Works |
| Thunderbird | Works |
Caveats (3)
- 1. Apple Mail: Only supported if you’ve updated your OS with Safari 17.5 or later.
- 2. Samsung Mail: Partial. Not supported with Hotmail/Outlook accounts.
- 3. HEY Mail, Proton Mail: Buggy. The function is supported but the color stays light even in dark mode.
Caveats as recorded by caniemail (MIT), one entry per wording.
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