Polymail - Native email app for email productivity.

CSS Peeper - Smart CSS viewer tailored for Designers.

Airmail - Airmail is a lightweight and lightning fast mail client for Mac.

Tailwind CSS - A utility-first CSS framework for rapidly building custom user interfaces.

Spark Mail - Spark helps you take your inbox under control. Instantly see what’s important and quickly clean up the rest. Spark for Teams allows you to create, discuss, and share email with your colleagues

Purgecss - Easily remove unused CSS