JSFiddle - React, Tailwind, and code Playground

HTML

<body>

<div id="Nav">
<ul class="accordionPart">
    <li>
        <div class="menu">AA</div>
        <div class="content">
            <ul class="sub">
                <li>   
                    <div class="menu">aa</div>
                    <div class="content">                        
                        <ul class="ter">
                            <li>
                                <div class="content">aaa</div>
                                <div class="content">aaa</div>
                                <div class="content">aaa</div>
                            </li>
                        </ul>
                    </div>
                    <div class="menu">aa</div>
                    <div class="content">                        
                        <ul class="ter">
                            <li>
                                <div class="content">aaa</div>
                                <div class="content">aaa</div>
                                <div class="content">aaa</div>
                            </li>
                        </ul>
                    </div>
                </li>
            </ul>
        </div>
    </li>
</ul>
</div>



</body>

CSS

ul, li{
margin:0;
padding:0;
list-style:none;
}

#Nav{
width:197px;
margin:0 auto;
}

#Nav ul.accordionPart {
background: #313132;
    color: #fdfdfd;
    font: bold 18px/32px Arial, sans-serif;
    text-decoration: none;
    text-shadow: 0px 1px 0px rgba(0,0,0, .35);
    display: block;
    box-shadow: inset 0px 1px 0px 0px rgba(255,255,255, .1), 0px 1px 0px 0px rgba(0,0,0, .1);
}

#Nav ul.accordionPart li .menu {
    padding-left:5px;
    color: #fff;
    cursor: pointer;
    font-family:Arial, Helvetica, sans-serif;
    font-size:18px;
    box-shadow: inset 0px 1px 0px 0px rgba(255,255,255, .1), 0px 1px 0px 0px rgba(0,0,0, .1);
}
#Nav ul.accordionPart li .menu_on {
    text-decoration: none;
    background:#7ade2a
}
#Nav ul.accordionPart li .content {
    margin: 6px 0 0;
    padding-left: 10px;
    color: #fff;
    cursor: pointer;
    font-family:Arial, Helvetica, sans-serif;
    font-size:14px;
    
}

JavaScript

$(function(){
        $('#Nav ul.accordionPart li div.menu').hover(function(){
            $(this).addClass('menu_on');
        }, function(){
            $(this).removeClass('menu_on');
        }).click(function(){
            $(this).next('div.content').slideToggle();
        }).siblings('div.content').hide();
    });