JSFiddle - React, Tailwind, and code Playground

HTML

<body>


<!-- Display Main Menu !-->
<nav class="cf">
  <nav class="cf">

    <!-- menu nav -->
    <ul class="topmenu">


      <!-- Home -->
      <li class="topmenu"><a href="/index.php">Home</a></li>



      <!-- Canada Equity ETF -->
      <li class="topmenu"><a href="/index.php#eqCanBroadMarket">Canada Equity <img src="/etf-images/down-arrow.jpg"></a>
        <ul class="submenu">
          <li><a href="/index.php#eqCanBroadMarket">Broad Market</a>                  
              <div class="submenu-wrapper">
              <ul class="sub-submenu">
                        <li><a href="/index.php#eqCanSS"> +++Third level menu option #1</a></li>
                        <li><a href="/index.php#eqCanREITS">+++Third level menu option #2</a></li>
                        <li><a href="/index.php#eqCanMC">+++Third level menu option #3</a></li>  
                  </ul>
              </div>
            
            </li>
                
          <li><a href="/index.php#eqCanSS">Sector Specific</a></li>
          <li><a href="/index.php#eqCanREITS">REITs (Real Estate Investment Trusts)</a></li>
          <li><a href="/index.php#eqCanMC">Mid-Cap and/or Small-Cap</a></li>         
          <li><a href="/index.php#eqCanMinVol">Minimum Volatility</a></li>
        </ul>
      </li>




      <!-- USA Equity ETF -->
      <li class="topmenu"><a href="/index.php#eqUSABroadMarket">USA Equity <img src="/etf-images/down-arrow.jpg"></a>
        <ul class="submenu">
          <li><a href="/index.php#eqUSABroadMarket">Broad Market</a></li>
          <li><a href="/index.php#eqNASDAQ">NASDAQ</a></li>
          <li><a href="/index.php#eqUSASmallCap">Small Cap</a></li>
          <li><a href="/index.php#eqUSASectorSpecific">Sector Specific</a></li>
          <li><a href="/index.php#eqUSAMinVol">Minimum Volatility</a></li>
          <li><a href="/index.php#eqUSAHighBeta">High Beta</a></li>
          <li><a href="/etfs-active.php">Actively Managed: USA Equity</a></li>
        </ul>
   ...

CSS

@charset "utf-8";
/* CSS Document */




html {
    background: #E6E3D4;
}




body {
    font: 100% Georgia, "Times New Roman", Times, serif;
    line-height: 1.2; /* */
}




/*micro-clearfix by Nicolas Gallagher http://nicolasgallagher.com/micro-clearfix-hack/*/
.cf:before, .cf:after {
    content:"";
    display:table;
}

.cf:after {
    clear:both;
}

/* For IE 6/7 (trigger hasLayout) */
.cf {
    zoom:1;
}





/* START top level menu: topmenu - works great */
/* START top level menu: topmenu - works great */
/* START top level menu: topmenu - works great */

ul.topmenu {
    margin: 0;
    padding: 0;
    list-style: none;
    float: left;
    background: #006da6; 
    height: 2em;
    width: 100%;

    font: 100% Georgia, "Times New Roman", Times, serif;
    font-size: 0.95em;

}
li.topmenu {
    margin: 0;
    padding: 0;
    list-style: none;
    float: left;
    position: relative;
}

/* ul.sub-submenu defined - newly added as part of my third level menu mod */
/* ul.submenu defined - works great */
/* ul.topmenu defined - great great */

ul.sub-submenu, ul.submenu, ul.topmenu li a {
    display: block;
    line-height: 1.8em;
    padding: 0 1em;
    color: white;
    text-decoration: none;
    z-index:3; 
}


ul.topmenu li a:hover, ul.topmenu li:hover > a {
    background: #035c7c;
    height: 1.8em;
    padding-top: .3em;
    position: relative;
    top: -.3em;
    border-radius: .3em .3em 0 0;
    text-decoration: none;
}


ul.current, a:hover.current, ul.topmenu li:hover a.current {
    background: #AD9B7F;
    background: yellow;
    color: #eee;
    padding-top: .3em;
    border-radius: .3em .3em 0 0;
    position: relative;
    top: -.3em;
    border-bottom: .3em solid #917F63;
    cursor: default;
}

ul.topmenu li:hover ul {
    left: 0;
}


/* END top level menu: topmenu - works great */
/* END top level menu: topmenu - works great */
/* END top level menu: topmenu - works great */




/* START level 2: submenu ... works great */
/* START...

JavaScript

$('.submenu li').hover(function() {
        $(this).find('ul').show();
    },
    function() {
      $(this).find('ul').hide();
});