Purgecss

vs

PostCSS

Tailwind CSS is a customizable, low-level HTML & CSS framework. With Tailwind CSS you can create unique UIs without having to write any CSS. The framework comes with pre-written CSS classes that you can add to HTML elements to build bespoke UI components, your way.

A modern responsive front-end framework based on Material Design. With Materialize CSS you can speedup your design and development process as most of the heavy lifting is done for you with default stylings that incorporate custom components. All principles of Material Design is incorporated into the framework and can be easily utilized with components and animations that provide better feedback to the users of your websites and applications.

Sass stands for syntactically awesome style sheets and is a mature, stable, and powerful CSS extension language. With Sass, web designers can work smarter and faster with CSS by providing a more elegant syntax for CSS and implementing various features that are useful for creating manageable stylesheets at scale. Some of these features include adding nested rules, variables, mixins, selector inheritance, and more. Sass has been active development since 2006, and continues to provide value to the web designer community until this day. It's released free and open-source under the MIT license.

UIkit A lightweight and modular front-end framework for developing fast and powerful web interfaces.