Jampack is a post-processing tool that takes the output of your Static Site Generator (aka SSG) and optimizes it for best user experience and best Core Web Vitals scores.

Stylify CSS is a library that uses CSS-like selectors to generate optimized Utility-First CSS dynamically based on what you write. It also allows you to define components, variables and global selectors.

Simple.css is a classless CSS framework that makes semantic HTML look good, really quickly. By classless it means that there are no CSS classes anywhere in the CSS or the HTML. So your website can look just like this using plain old vanilla HTML.