Tailwind CSS is an utility-first CSS framework for rapidly building custom designs with predefined class. If you are a big fan like me, you will probably appreciate this nice cheat-sheet made by Jay Elaraj.
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Tailwind CSS 3.0
Rapidly build modern websites without ever leaving your HTML. A utility-first CSS framework packed with classes like flex, pt-4, text-center and rotate-90 that can be composed to build any design, directly in your markup.
Protomaps
Protomaps is an open source map of the world, deployable as a single static file on cloud storage.
Lodash
A modern JavaScript utility library delivering modularity, performance and extras.