flexbox-css is a collection of utility classes named to match the CSS flexbox styles. The stylesheet is completely vendor prefixed and also has responsive variants of the classes. It is useful for building flexbox based pages with good cross-browser support.
You can either yarn add flexbox-css@3.1.1/npm install --save flexbox-css@3.1.1 and use a CSS loader to load the file, or use a CDN like rawgit to load the latest version
<link rel="stylesheet" href="https://cdn.rawgit.com/moodysalem/flexbox-css/e5a121cb493c0452509708a9fb0524c671f31b4e/dist/flexbox-css-min.css" integrity="sha384-W3cb5bRHJiWSSwBvBHgWXGH8SdPZU6tA7DAa0S0JHJdvRlBqeKWBya2Lu9zrUMXK" crossorigin="anonymous">