Cerberus
Patterns for responsive HTML email templates and newsletters
... for HTML email. The code is meant to be edited, adapted, and built upon. The code is compartmentalized and annotated in an effort to explain what’s happening so you can add, edit, and remove code with some confidence. This has been tested in all “popular” email clients, but not every email client out there. Good for simple layouts such as transactional and single-column emails.