| CSS support test (green = supported, red = not) |
| 1. <style> class | class |
| 2. @media query | media |
| 3. @supports | supports |
| 4. attribute selector | attribute |
| 5. child combinator | child |
| 6. CSS variables | var() |
| 7. rgba() | rgba |
| 8. hsl() | hsl |
| 9. linear-gradient | gradient |
| 10. ::before content | ::before |
| 11. border-radius | |
| 12. box-shadow | |
| 13. display:flex (row) | |
| 14. display:grid (2 cols) | |
| 15. max-width (half green = yes) | half |
| 16. @font-face web font | Hamburgefonstiv |
| 17. position:absolute | |
| 18. opacity | opacity |
| 19. text-shadow | shadow |
| 20. :not() selector | not() |
|
| End of test. MailSlurp email client support report, v1. |