JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
  <li class="item-1"><a href="">Search</a></li>
</ul>

CSS

ul {
    list-style: outside none none;
}

ul > li {
    float: left;
}
ul > li {
    display: block;
    position: relative;
}

ul > li > a {
  display: block;
  text-decoration: none;
  font-size:0;
  border-radius: 50px;
  text-align: center;
  height: 50px;
  width: 50px;
  border: 2px solid #ccc;
  background:linear-gradient(to left, transparent 50%, rgba(0,0,0,0.2) 50%),linear-gradient(to top, transparent 50%, rgba(0,0,0,0.2) 50%)
}

ul > li > a:before {
  font-family:"Glyphicons Halflings";
  font-size: 50px;
  display:flex;
  height:100%;
  width:100%;
  align-items:center;
  justify-content:center;
}

ul > li.item-1 > a:before {
  content:"\2b";
}