Style <a>, <button> and <input type="subtmit"> elements by adding the
class btn. Different variants are also available.
<a href="" class="btn">Anchor element</a>
<button>Button element</button>
<input type="submit" class="btn" value="Submit element">
Option to increase button size
<a href="" class="btn large">Large button</a>
Option to change color and style.
<a href="" class="btn cta">Call to action</a>
<a href="" class="btn outline">Outline</a>
<a href="" class="btn link">Link</a>