JSFiddle - React, Tailwind, and code Playground

HTML

<a href="#" class="foo" onclick="this.className='foo_clicked';" tabindex="0" onBlur="this.className='foo';" >Transition me!</a>

CSS

a.foo {
  padding: 5px 10px;
  background: #9c3;
  -webkit-transition: background 0.3s ease;
  -moz-transition: background 0.3s ease;
  -o-transition: background 0.3s ease;
  transition: background 0.3s ease;
}

a.foo_clicked {
  padding: 5px 10px;
  background: #690;
  -webkit-transition: background 0.3s ease;
  -moz-transition: background 0.3s ease;
  -o-transition: background 0.3s ease;
  transition: background 0.3s ease;
}

a.foo:hover
{  background: #690;
}