RegExr is an online tool to learn, build, & test Regular Expressions (RegEx / RegExp).
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Free Books for Designers
Free ebooks to help you develop creative and design skills.
A methodology to help you write human-friendly CSS. C3 (Component, Child, Context) is a methodology for writing CSS, centred around a selector naming convention. This approach is intended for anyone who wants to write code which is semantic, easy to maintain, and scalable. If you are familiar with BEM, you will be familiar with two thirds of C3. Either way, you should find all the information you need in this guide.
Complete Guide to Media Queries
Media queries are what make modern responsive design possible. With them you can set different styling based on things like a users screen size, device capabilities or user preferences. But how do they work, which ones are there and which ones should you use? Here's the complete guide to media queries.
Build your own React
Rewrite React from scratch. Step by step. Following the architecture from the real React code but without all the optimizations and non-essential features.
The Typing of the RegEX
Do you dare to discover the horrors that await! Test your RegEX skills with this challenging game.
Web Browser Engineering
Oh My Git!
An open source game about learning Git! Oh My Git! is an open source game that introduces players to the popular version control system "Git". It is highly interactive, and aims at building intuition for operations like "merging" or "rebasing" branches. Players are guided through the features of Git step by step – each level tells a little story where the player can use their new-found powers to solve problems or help others.
CUBE CSS is a CSS methodology that’s orientated towards simplicity, pragmatism and consistency. It’s designed to work with the medium that you’re working in—often the browser—rather than against it.
cheat allows you to create and view interactive cheatsheets on the command-line. It was designed to help remind *nix system administrators of options for commands that they use frequently, but not frequently enough to remember.
A fun spin practicing regex. Build your skills by playing Regex Crossword.
Your job is to stop the incoming enemies from getting past your defenses. Unlike other tower defense games, you must position your towers using CSS!