Bootstrap - Simple and flexible HTML, CSS, and JS for popular UI components and interactions
Svelte - Cybernetically enhanced web apps
Material UI - A CSS Framework and a Set of React Components that Implement Google's Material Design
Glimmer - Fast and light-weight UI components for the web
Selectize.js - Selectize is a custom <select> UI control with autocomplete and native-feeling keyboard...
Preact.js - Preact is a fast 3kB alternative to React with the same modern API. Components & Virtual DOM.