JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="clearfix">
  <li><a href="#">1</a></li>
  <li><a href="#">2</a></li>
  <li><a href="#">3</a></li>
</ul>

CSS

clearfix::before,.clearfix::after {
  content: " ";
  display: table;
}

.clearfix::after {
  clear: both;
}

ul {
  margin: 0;
  padding: 0;
}

ul li {
  box-sizing: border-box;
  border-right: 1px solid #000;
  float: left;
  list-style: none;
}

.tabbez li:last-of-type {
  border-right: none;
}

ul li a {
  background-color: #f00;
  color: #fff;
  display: block;
  line-height: 50px;
  text-align: center;
  text-decoration: none;
  width: 50px;
}