CodePen.io,网站前端设计开发平台，codepen.io工具提供多种效果的网站前端代码设计工具
CodePen is all about front end code inspiration and education through sharing. In the editor, enter HTML, CSS, and javascript and the combined result is displayed below. Save your Pen, share it, and explore others. This is extremely useful for showing off your work, troubleshooting, demonstrating bugs, or anything else you can think of.
From the editor, you can click the Share button for a dropdown with a link to a full page result of your Pen. You can use that to test things you build in older browsers if need be.CodePen.io
