What's this for?
Postmark Transactional Email Templates are rock-solid email templates that render beautifully in tons of email clients. They provide the foundation of our Postmark Templates feature, and we're glad to provide them as Open Source to the wider community.
Inline the CSS
For client compatibility, HTML emails should always be inlined before sending.
If you choose to send your emails with Postmark, each time you send we will automagically inline the CSS for you.