Awesome Design

If you want to contribute please submit a PR and will review the added links to maintain a high quality of curated frameworks, design systems and others.

Design Frameworks
Very Lightweight
General Purpose
Material Design
Specialized
Toolkits
Stalled Development

We start with design systems obviously.

🔱 List of design systems

Artsy - Web-based framework for rapid prototyping and building larger web projects.
Docs, Repo
Uber Design System - Uber design system. Docs, Repo
**US Government design system ** - US Gov design system. Docs, Repo
**UK Gov design system ** - UK gov design system. Docs, Repo
Salesforce - Salesforce design system. Repo | #SCSS
inuitcss - Extensible, scalable, Sass-based, OOCSS framework for large and long-lasting UI projects.
Repo | #SCSS

List of CSS frameworks. [Updated regularly 🔜 🕐]

Very Lightweight

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.
Docs, Repo | #Sass
Picnic CSS - Lightweight and beautiful library.
Demo, Docs, Repo | #SCSS
mini.css - Minimal, responsive, style-agnostic CSS framework.
Docs, Repo | #SCSS
sakura - Minimal classless CSS framework/theme.
Demo, Repo | #SCSS
Wing - Beautiful CSS framework designed for minimalists.
Repo | #Stylus
Marx - Classless CSS reset.
Docs, Repo | #SCSS #Stylus
Tacit - CSS framework for dummies, without classes.
Repo | #SCSS
awsm.css - CSS library for semantic HTML markup without classes, attributes, etc.
Demo, Repo | #SCSS
Chota - Really small CSS framework.
Repo | #CSS
Frowcss - Frow is an open source HTML and CSS framework for creating quick & responsive projects on the web, powered by Flexbox. Docs, Repo | #CSS

General Purpose

Bootstrap - The most popular HTML, CSS, and JavaScript framework for developing responsive, mobile first projects on the web.
Demo, Docs, Themes, Repo | #SCSS
Semantic UI - User interface is the language of the web.
Note: The project seems to be inactive but there is an active fork called Fomantic UI.
Docs, Repo | #LESS
Bulma - Modern CSS framework based on Flexbox.
Demo, Docs, Repo | #Sass
Foundation - The most advanced responsive front-end framework in the world.
Demo, Docs, Repo | #SCSS
UIkit - Lightweight and modular front-end framework for developing fast and powerful web interfaces.
Demo, Docs, Repo | #LESS #SCSS
Spectre.css - Lightweight, responsive and modern CSS framework.
Docs, Repo | #SCSS
Primer - CSS framework that powers GitHub's front-end design.
Docs, Repo | #SCSS
Tachyons - Quickly build and design new UI without writing CSS.
Demo, Docs, Repo | #CSS
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
Carbon Components - Component library behind IBM's Carbon Design System.
Docs, Repo | #SCSS
PatternFly - UI framework for enterprise web applications.
Demo, Docs, Repo | #SCSS #LESS
turretcss - Responsive front-end framework for accessible and semantic websites.
Demo, Docs, Repo | #CSS
HiQ - Simple CSS foundation with responsive typography and input styling.
Docs, Repo | #PostCSS
Tawian - A markdowny CSS framework Docs, Repo | #CSS
Papercss - The Less Formal CSS Framework Docs, Repo | #CSS
Hackcss - Dead simple CSS framework. Docs, Repo | #CSS

Material Design

Material Components Web - Modular and customizable Material Design UI components for the web.
Demo, Docs, Repo | #SCSS
Materialize - CSS framework based on material design.
Demo, Docs, Repo | #SCSS
MUI - Lightweight CSS framework that follows Google's Material Design guidelines.
Docs, Repo | #SCSS
Propeller - Front-end responsive framework based on Google's Material Design standards & Bootstrap.
Docs, Repo | #SCSS

Specialized

Tailwind CSS - Utility-first CSS framework for rapid UI development.
Docs, Repo | #CSS
Gutenberg - Modern framework to print the web correctly.
Demo, Repo | #SCSS
Tufte CSS - Style your webpage like Edward Tufte’s handouts.
Repo | #CSS
Bojler - Email framework for developing responsive and lightweight email templates.
Docs, Repo | #SCSS
Quasar - High Performance Full Frontend Stack Docs, Repo | #SCSS

Vintage & Retro

NES.css - NES-style CSS Framework.
Docs, Repo | #SCSS
TerminalCss - Modern and minimalistic CSS framework for terminal enthusiasts. Please use the green color to be an authentic hacker-style CL Docs, Repo | #CSS
BOOTSTRA.386 - A vintage 1980s DOS inspired Twitter Bootstrap theme Demo, Repo | #CSS
PSone - PS1 style CSS Framework, inspired by NES.css Demo, Repo | #CSS
RPGUI - Lightweight framework for old-school RPG GUI in web! Demo, Repo | #CSS
GEO bootstrap - A timeless Twitter Bootstrap theme built for the modern web. Docs, Repo | #CSS

Toolkits

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, Scaffold | #SCSS
Neat - Lightweight and flexible Sass grid.
Demo, Docs, Repo | #SCSS

Stalled Development

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.

Show Section

Material Design Lite - Material Design components in HTML/CSS/JS.
Demo, Docs, Repo
Skeleton - Dead simple, responsive boilerplate.
Demo, Docs, Repo
Compass - Open-source CSS authoring framework.
Docs, Repo
Flexbox Grid - Grid based on CSS3 flexbox.
Repo
Basscss - Low-level CSS toolkit.
Repo
Mobi.css - Lightweight, scalable, mobile-first CSS framework.
Docs, Repo | #CSS
Pills - Simple responsive CSS Grid for humans.
Repo
Cutestrap - Sassy, opinionated CSS framework, a tiny alternative to Bootstrap.
Repo
unsemantic - Fluid grid for mobile, tablet, and desktop.
Demo, Docs, Repo
Kube - Web framework for professional developers and designers.
Docs, Repo | #SCSS
Concise CSS - Give up the bloat. Stop tripping over your classes. Be concise.
Docs, Repo | #SCSS
Scooter - SCSS framework & UI library for Dropbox web.
Repo
Responsive Boilerplate - Powerful, accessible, developer friendly framework for building responsive websites.
Docs, Repo | #SCSS
Centurion - Web-based framework for rapid prototyping and building larger web projects.
Docs, Repo