By Adobe: React Spectrum includes three libraries: React Spectrum — A React implementation of Spectrum, Adobe’s design system. React Aria — A library of React Hooks that provides accessible UI primitives for your design system. React Stately — A library of React Hooks that provides cross-platform state management and core logic for your design system. […]
98.css is a CSS library for building interfaces that look like Windows 98. 😂 98.css → UPDATE 2020.04.28: Jordan Scale, the author of the library, has done a write-up on 98.css.