JS library interface style examples (React focused)

example.html

<!-- Material-ui  -->
<Button variant="contained" color="primary">
  Hello world
</Button>

<!-- Semantic UI -->
<button class="ui button">Follow</button>

<!-- React bootstrap -->
<Button variant="primary">Primary</Button>

<!-- Shards React -->
<Button outline theme="secondary">
  Hello world
</Button>

<!-- Evergreen -->
<Button appearance="primary">Hi Evergreen!</Button>

<!-- Elemental UI -->
<Button type="primary">Primary</Button>