JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
  <li>
    Estonian<span class="arrow-down"></span>
    <ul>
      <li><a href="#">Estonian</a></li>
      <li><a href="#">English</a></li>
    </ul>
  </li>
</ul>

CSS

ul {
  text-align: left;
  display: inline;
  margin: 0;
  padding: 15px 4px 17px 0;
  list-style: none;
}
ul li {
  font: bold 12px/18px sans-serif;
  display: inline-block;
  margin-right: -4px;
  position: relative;
  padding: 15px 20px;
  background: #2980b9;
  cursor: pointer;
  -webkit-transition: all 0.2s;
  -moz-transition: all 0.2s;
  -ms-transition: all 0.2s;
  -o-transition: all 0.2s;
  transition: all 0.2s;
  color: #fff;
}
ul li:hover {
  background: #555;
  color: #fff;
}
ul li ul {
  padding: 0;
  position: absolute;
  top: 48px;
  left: 0;
  width: 150px;
  -webkit-box-shadow: none;
  -moz-box-shadow: none;
  box-shadow: none;
  display: none;
  opacity: 0;
  visibility: hidden;
  -webkit-transiton: opacity 0.2s;
  -moz-transition: opacity 0.2s;
  -ms-transition: opacity 0.2s;
  -o-transition: opacity 0.2s;
  -transition: opacity 0.2s;
}
ul li ul li {
  min-width: 80px;
  background-color: #555;
}
ul li ul li > a { 
  text-decoration: none;
  display: block; 
  color: #fff;
}
ul li ul li:hover {
    background: #666;
}
ul li:hover ul {
  display: block;
  opacity: 1;
  visibility: visible;
}
ul li > span {
	display: inline-block;
	margin: 0 0 -3px 5px;
	width: 12px;
	height: 12px;
	background-image: url('https://cdn2.iconfinder.com/data/icons/ios-7-icons/50/down4-24.png');
	background-size: 12px 12px;
}