The most advanced responsive front-end framework in the world. Quickly create prototypes and production code for sites that work on any kind of device.

Font files available from Google Fonts, and a public issue tracker for all things Google Fonts

Emoji for everyone. https://twemoji.twitter.com/

📚 Community guides for open source creators

Loading icons and small animations built with pure SVG.

Pattern matching syntax for ECMAScript

CSS Reference: a free visual guide to the most popular CSS properties

CSS custom properties to help accelerate adaptive and consistent design.

A strong, neutral, principles-driven, open source typeface for text or display

Learn the basics of web design in 4 minutes

A classless CSS framework to write modern websites using only HTML.

Provides standard objects and functions for working with dates and times.

A curated list of awesome articles, websites and resources about mental health in the software industry.

Polyfill for CSS `position: sticky`

Color combination contrast tester

PARTY OR DIE

Parse web pages using CSS query selectors

Nullish coalescing proposal x ?? y

🚲 Contribute to the open source community every Friday

An increasingly less-brief guide to Mastodon

Open Source Icons for the Web

A truly naked, brutalist html quine

React UI component design tool

Open source for http://trumptracker.github.io/

InlineTweet.js allows you to easily create tweetable links out of any text on a webpage

At the intersection of art and bad performance

Saving the web 1kb at a time. Is your CSS file getting too big?