Bootstrap is the most popular HTML, CSS, and JS framework for developing responsive, mobile first projects on the web. Bootstrap is open source.
With Bootstrap, you get extensive and beautiful documentation for common HTML elements, dozens of custom HTML and CSS components, and awesome jQuery plugins.
Bootstrap supports the latest, stable releases of all major browsers and platforms. On Windows, it supports Internet Explorer 10-11 / Microsoft Edge.
Bootstrap display and function correctly in alternative browsers which use the latest version of WebKit, Blink, or Gecko, whether directly or via the platform's web view API, but are not explicitly supported.