Semantic UI
Semantic empowers designers and developers by creating a shared vocabulary for UI.
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The framework powering the Elastic Stack.
Framework mixing fully customizable components & utility-first classes, leaving the design choice to the developer.
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Halfmoon is a highly customizable, drop-in Bootstrap replacement.
Tailwind CSS is a utility-first CSS framework for rapidly building modern websites without ever leaving your HTML.
Bulma is a free, open source CSS framework based on Flexbox and built with Sass.