JSFiddle - React, Tailwind, and code Playground

HTML

<ul id="menu">
  <li><a href="#">Browsers</a>
      <ul>
        <li><a href="#">Firefox</a></li>
        <li><a href="#">Google Chrome</a></li>
        <li><a href="#">Internet Explorer</a></li>            
        <li><a href="#">Opera</a></li>
        <li><a href="#">Safari</a></li>
    </ul>
  </li>
  <li><a href="#">Editors</a>
      <ul>
          <li><a href="#">Sublime Text 2</a></li>
          <li><a href="#">TextMate</a></li>            
          <li><a href="#">Visual Studio</a></li>
          <li><a href="#">WebStorm</a></li>
    </ul>
  </li>
  <li><a href="#">Languages</a>
      <ul>
          <li><a href="#">C#</a></li>
          <li><a href="#">CoffeeScript</a></li>            
          <li><a href="#">JavaScript</a></li>
          <li><a href="#">Ruby</a></li>
          <li><a href="#">Visual Basic</a></li>
      </ul>
  </li>
</ul>

CSS

/* http://www.kriesi.at/archives/create-a-multilevel-dropdown-menu-with-css-and-improve-it-via-jquery */
  
  #menu, #menu ul {
    margin: 0;
    padding: 0;
    list-style-type: none;
    list-style-position: outside;
    position: relative;
    line-height: 1.5em;
  } 
  #menu a:link, #menu a:active, #menu a:visited{
    display: block;
    padding: 0px 5px;
    border: 1px solid #333;
    color: #fff;
    text-decoration: none;
    background-color: #333;
  }

  #menu a:hover {
    background-color: #fff;
    color: #333;
  }  
  
  #menu li {
    float: left;
    position: relative;
  }
  
  #menu ul {
    position: absolute;
    width: 12em;
    top: 1.5em;
    display: none;
  }
  
  #menu li ul a {
    width: 12em;
    float: left;
  }
  
  #menu ul ul{
    top: auto;
  }

  #menu li ul ul {
    left: 12em;
    margin: 0px 0 0 10px;
  }

JavaScript

$( document ).ready( function() {

  $( "#menu li" ).hover( 
    function() {
      $( this ).find( "ul" )
        .stop( true, true )
        .slideToggle();
    },
    function() {
      $( this ).find( "ul" )
        .stop( true, true )
        .slideUp();
    });
  
});