Does CodePen support JavaScript?

You can add JavaScript libraries to your Pen through the JavaScript settings menu . There are two ways to access the JavaScript settings menu. For quickest access, click the gear icon in the upper left of the JS editor panel. That opens the Pen Settings menu with the JavaScript tab automatically selected.

Read more

How do I add files to Codepen?

#Creating and Uploading Files Give the file a name and file extension in the yellow text field. To create a file inside a specific directory, click the directory first, then click the “New File” button . Drag and drop individual files into the Project Root, or into directories within the project.

Read more