CodePen: The best place to build, test, and discover front-end code. CodePen is a social development environment for front-end designers and developers. Build and deploy a website, show off your work, build test cases to learn and debug, and find inspiration.
CSSBattle: CSS code-golfing is here! Use your CSS skills to replicate targets with smallest possible code. Feel free to check out the targets below and put your CSS skills to test.