JSFiddle - React, Tailwind, and code Playground

HTML

<ul id="nav-sub">
    <li class="sub-level-0"><a href="#">Menu Item One</a>
    <ul>
        <li class="sub-level-1"><a href="#">Sub Menu Item One</a></li>
        </ul>
      </li>
     <li class="sub-level-0"><a href="#">Menu Item Two</a>   
      <ul>
                <li class="sub-level-1"><a href="#">Sub Menu Item One</a></li>
                <li class="sub-level-1"><a href="#">Sub Menu Item Two</a></li>
      </ul>  
      </li>    
</ul>

JavaScript

$(document).ready(function() {
    //hide all SUB elements
    $(".sub-level-1").hide(); 
    //attach click to top elements only
    $("li.sub-level-0").mousedown(function(evt) {
        //find the sub element and toggle it..
       if(($(evt.target).text().indexOf("Sub"))!=0) {//Bad hack! sry =(
        $(this).find("ul .sub-level-1").slideToggle();
      }
    });

});