List of awesome CSS frameworks.
Feel free to contribute.

Supported by FrontAid CMS:

• Base / Reset / Normalize
• Class-less
• Very Lightweight
• General Purpose
• Material Design
• Utility-based
• Specialized
• Toolkits
• Stalled Development

• sanitize.css - The best-practices CSS foundation.
  Repo | #CSS

• modern-normalize - Normalize browsers' default style.
  Repo | #CSS

• minireset.css - Tiny modern CSS reset.
  Repo | #Sass

• modern-css-reset - Tiny little reset that you can use as the basis of your CSS projects.
  Repo | #CSS

• inuitcss - Extensible, scalable, Sass-based, OOCSS framework for large and long-lasting UI projects.
  Repo | #SCSS

• ress - Modern CSS reset.
  Repo | #CSS

• Natural Selection - Collection of best-practice CSS selectors.
  | #CSS

Frameworks that use semantic HTML and do not rely on classes.

• Water.css - Just-add-CSS collection of styles to make simple websites just a little nicer.
  Repo | #CSS

• MVP.css - Minimalist stylesheet for HTML elements.
  Docs, Repo | #CSS

• sakura - Minimal classless CSS framework/theme.
  Demo, Repo | #SCSS

• Tacit - CSS framework for dummies, without classes.
  Repo | #SCSS

Frameworks that are smaller than ~5KB.

• Pure - Set of small, responsive CSS modules that you can use in every web project.
  Demo, Docs, Repo | #CSS

• Milligram - Minimalist CSS framework.
  Demo, Docs, Repo | #Sass

• Picnic CSS - Lightweight and beautiful library.
  Demo, Docs, Repo | #SCSS

• Chota - Really small CSS framework.
  Demo, Docs, Repo | #CSS

• Bootstrap - The most popular HTML, CSS, and JavaScript framework for developing responsive, mobile first projects on the web.
  Demo, Docs, Repo | #SCSS

• Bulma - Modern CSS framework based on Flexbox.
  Demo, Docs, Repo | #Sass

• Foundation - The most advanced responsive front-end framework in the world.
  Docs, Repo | #SCSS

• UIkit - Lightweight and modular front-end framework for developing fast and powerful web interfaces.
  Demo, Docs, Repo | #LESS #SCSS

• Primer - CSS framework that powers GitHub's front-end design.
  Docs, Repo | #SCSS

• Carbon Components - Component library behind IBM's Carbon Design System.
  Docs, Repo | #SCSS

• Fomantic-UI - Build beautiful websites fast, with concise HTML, intuitive javascript, and simplified debugging.
  Docs, Repo | #LESS

• Pico.css - Elegant styles for all native HTML elements, dark mode automatically enabled.
  Demo, Docs, Repo | #SCSS

• Blaze UI - Open source modular toolkit providing great structure for building websites quickly with a scalable and maintainable foundation.
  Demo, Docs, Repo | #SCSS

• Base - Rock solid, responsive HTML/CSS framework.
  Docs, Repo | #SCSS #LESS

• Cirrus - Component and utility centric SCSS framework designed for rapid prototyping.
  Demo, Docs, Repo | #CSS

• turretcss - Responsive front-end framework for accessible and semantic websites.
  Demo, Docs, Repo | #CSS

• Vanilla Framework - Simple, extensible CSS framework. Written by the Canonical Web Team.
  Demo, Docs, Repo | #SCSS

• PatternFly - UI framework for enterprise web applications.
  Demo, Docs, Repo | #SCSS #LESS

• HiQ - Simple CSS foundation with responsive typography and input styling.
  Docs, Repo | #PostCSS

• Material Components Web - Modular and customizable Material Design UI components for the web.
  Demo, Docs, Repo | #SCSS

• MUI - Lightweight CSS framework that follows Google's Material Design guidelines.
  Docs, Repo | #SCSS

• Materialize - Responsive front-end library based on Google's Material Design.
  Docs, Repo | #SCSS

• Tailwind CSS - Utility-first CSS framework for rapid UI development.
  Docs, Repo | #CSS

• Tachyons - Quickly build and design new UI without writing CSS.
  Demo, Docs, Repo | #CSS

• Open Props - CSS custom properties to help accelerate adaptive and consistent design.
  Demo, Docs, Repo | #CSS #PostCSS

• NES.css - NES-style CSS Framework.
  Demo, Docs, Repo | #SCSS

• 98.css - CSS library for building interfaces that look like Windows 98.
  Repo | #CSS

• Tufte CSS - Style your webpage like Edward Tufte’s handouts.
  Repo | #CSS

• Gutenberg - Modern framework to print the web correctly.
  Demo, Docs | #SCSS

• XP.css - CSS library for building interfaces that look like Windows XP.
  Repo | #PostCSS

• Bojler - Email framework for developing responsive and lightweight email templates.
  Docs, Repo | #SCSS

• TuiCss - Library to create MS-DOS interfaces.
  Demo, Docs | #SCSS

• 7.css - CSS library for building interfaces that look like Windows 7.
  Repo | #PostCSS

Toolkits are closer to a library than to a framework. They do not provide actual styling but utilities (e.g. mixins) that you can use in your CSS preprocessor.

• Bourbon - Lightweight Sass tool set.
  Docs, Repo | #SCSS

Frameworks that have not seen any real development for more than about one year or officially have been deprecated. We are keeping them here for reference/inspiration and hope for a revival.

License CC0 1.0:

You can copy, modify, distribute and perform the work, even for commercial purposes, all without asking permission.

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