JSFiddle - React, Tailwind, and code Playground

HTML

<span class="button on">ON</span>
<span class="button off">OFF</span>

CSS

.button{
  padding: 2px 4px;
  border-radius: 3px;
  color: white;
  font-size: 11px;
}
.on { background: red;   }
.off{ background: green; }