CSS is powerful, you can do a lot of things without JS.

JavaScript Design Patterns

HTML Standard

Simple wrapper for cross-browser usage of the JavaScript Fullscreen API

Test suites for Web platform specs — including WHATWG, W3C, and others

Assorted CSS and UI experiments.

Web Components specifications

🔖 lightweight, efficient Tags input component in Vanilla JS / React / Angular / Vue

Turning web forms into conversations

Style tools for UI components

A Fast & Light Virtual DOM Alternative

Feature.js is a fast, simple and lightweight browser feature detection library in 1kb.

A collection of helpful snippets to use inside of browser devtools

HTTPLeaks - All possible ways, a website can leak HTTP requests

🔥 Starter Files to Learn with ES6 for Everyone

Performant, fully fluid headings

The HTML5 template that goes back to basics

A bunch of demos for different web font loading strategies. Companion to https://www.zachleat.com/web/comprehensive-webfonts/

jQuery plugin to resize images to fit in a container.

Universal CSS for web printing

small and sleek mobile navigation

Visualize your CommonJS or AMD module dependencies in a force directed graph report.

A tiny script for accessible content toggles.

A simple javascript plugin to show people how to say your name correctly.

Pragmatist's Guide to Service Worker

Serverless peer to peer chat on WebRTC

Component CSS for grids

How a "security" tab in the browsers developer tools might work.

Cool browser sync example exposing localhost to external domain

PostCSS plugin to scale values from one range to another.