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Bulma
Bulma is an open source CSS framework based on Flexbox and built with Sass. It’s 100% responsive, fully modular, and available for free.
19 Alternatives To Bulma
Angular Material
Angular Material is both a UI Component framework and a reference implementation of Google’s Material Design Specification.
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Bootstrap
Simple and flexible HTML, CSS, and JS for popular UI components and interactions
Element UI
Element, a Vue 2.0 based component library for developers, designers and product managers.
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Foundation
The most advanced responsive front-end framework in the world
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Gridlex
Simple. Robust. Responsive. Flexible.
HTML5 Boilerplate
A rock-solid default for HTML5 awesome.
Lit
World’s smallest responsive CSS framework (398 bytes!)
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Material-UI
A CSS Framework and a Set of React Components that Implement Google’s Material Design
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Milligram
A minimalist CSS framework
Polymer
Polymer is a library that uses the latest web technologies to let you create custom HTML elements.
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Purecss
A set of small, responsive CSS modules that you can use in every web project.
Semantic UI
A UI Component library implemented using a set of specifications designed around natural language
Spectre
Spectre is a web application to diff screenshots.
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UIKit
A lightweight and modular front-end framework for developing fast and powerful web interfaces
Unnamed
A colorful CSS framework made by a human not an AI
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Vuetify
Material Component Framework for VueJS 2
WING
A phone carrier that is actually nice to you.
w2ui
W2UI is a small JavaScript UI library with a complete set of widgets: layout, grid, sidebar, toolbar, tabs, fields, popup, utilities.