JSFiddle - React, Tailwind, and code Playground

by fparent

HTML

<button class="fc-button-ranking rank-up"></button>
<br /><br />
<button class="fc-button-ranking rank-down"></button>

CSS

.fc-button-ranking {
  width: 40px;
  height: 20px;
  display: block;
  background-color: transparent;  
  border: 0;
  position: relative;
}

.fc-button-ranking:after {
  width: 0;
  height: 0;
  content: "\0020";
  position: absolute;
  top: 0;
  left: 0;
}

.fc-button-ranking.rank-up:after {
  border-top: 20px solid red;
  border-left: 20px solid transparent;
  border-right: 20px solid transparent;
  border-bottom: 0;
}

.fc-button-ranking.rank-down:after {
  border-top: 0;
  border-left: 20px solid transparent;
  border-right: 20px solid transparent;
  border-bottom: 20px solid red;
}