Postmark supports Tailwind CSS

Postmark is an email delivery service for developers. It sends the messages your application depends on (password resets, receipts, notifications, newsletters) through an API or SMTP, with libraries for nearly every language so it fits into whatever stack you're already running. The low-level work that decides whether an email reaches the inbox (IP reputation, blocklists, feedback loops, reverse DNS) is handled for you, and you can start sending within minutes.

Transactional and promotional email never share infrastructure. Postmark routes the two through completely separate sending streams, so a marketing send can't drag down the deliverability of a password reset someone is waiting on right now. Strong deliverability comes standard, without a dedicated IP and without a sales call, and every new sender is vetted so spammers never get a foothold.