Generate properly structured, production-grade email HTML. Use this skill whenever creating, editing, or reviewing HTML emails — marketing campaigns, transactional emails, automated flows, newsletters. Covers mobile-first responsive patterns, dark mode handling, Outlook conditional comments, image-to-text ratio for spam filters, preheader optimization, and the structural details that LLMs get catastrophically wrong when generating email HTML from general training data. Trigger on: "design an email", "email HTML", "email template", "responsive email", "email dark mode", "outlook email", "email rendering", or any request to create HTML that will be sent via email.
2026-05-17