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 moreHow do you add CSS to CodePen?
To add a preprocessor to your Pen, click the settings “gear” icon at the top of the CSS editor panel . The Pen Settings will open with the CSS tab automatically selected. You can also open Pen Settings from the button in the header.
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