CSS-in-JS with build time generated styles, RSC compatible, multi-variant support, and best-in-class developer experience.

Spectre.css is described as 'Lightweight, responsive and modern CSS framework for faster and extensible development' and is a CSS Framework in the development category. There are more than 50 alternatives to Spectre.css for a variety of platforms, including Web-based, Self-Hosted, Mac, Windows and Linux apps. The best Spectre.css alternative is Bootstrap, which is both free and Open Source. Other great apps like Spectre.css are Tailwind CSS, Bulma, Semantic UI and Foundation.
CSS-in-JS with build time generated styles, RSC compatible, multi-variant support, and best-in-class developer experience.

Create beautiful, responsive & accessible web apps quickly with Vue or Nuxt. Nuxt UI is an open-source UI library of 100+ customizable components built with Tailwind CSS and Reka UI.




Skeleton is a small collection of CSS & JS files that can help you rapidly develop sites that look beautiful at any size, be it a 17" laptop screen or an iPhone. Skeleton is built on three core principles:
A set of beautifully-designed, accessible components and a code distribution platform. Works with your favorite frameworks. Open source. Open code.

Front-end framework with a built-in dark mode and full customizability using CSS variables; great for building dashboards and tools.
A unified, HTML5-based user interface system for all popular mobile device platforms, built on the rock-solid jQuery and jQuery UI foundation. Its lightweight code is built with progressive enhancement, and has a flexible, easily themeable design.


Stylify is a library that generates utility-first CSS dynamically based on what you write. Write HTML. Get CSS 🚀.




Topcoat is a brand new open source CSS library designed to help developers build web apps with an emphasis on speed. It evolved from the Adobe design language developed for Brackets, Edge Reflow, and feedback from the PhoneGap app developer community.
Topcoat is the most popular Windows, Mac & Linux alternative to Spectre.css.
EFY allows you to customize the design of your html based apps or websites from an UI sidebar menu and combine billions of possible patterns. You can also create, share or import json themes for easier access. All apps that use efy can share the same theme or individual themes.




Eva Design System is a free and open-source, customizable design system. Available for Sketch with Mobile and Web component libraries.

This project's goal is to be able to create a fully accessible material design styled website using React Components and Sass.

Metro UI CSS a set of styles to create a site with an interface similar to Windows 8.