JSFiddle - React, Tailwind, and code Playground

HTML

<div id="leftWrap">
    <ul id="accordion">
        <li>
            <div>Absorption</div>
            <ul style="display: none;">
                <li><a href="c-77-accessories.aspx">Accessories</a><ul>
                    <li><a href="c-81-aa500afg.aspx">AA500AFG</a></li>
                    <li><a href="c-79-aa500f.aspx">AA500F</a></li>
                    <li><a href="c-80-aa500g.aspx">AA500G</a></li>
                    <li><a href="c-78-aa990f.aspx">AA990F</a></li>
                    </ul>
                </li>
                <li><a href="c-82-consumables.aspx">Consumables</a></li>
                <li><a href="c-76-products.aspx">Products</a></li>
            </ul>
        </li>
        <li>
            <div>Fluorescence</div>
            <ul style="display: none;">
                <li><a href="c-101-accessories.aspx">Accessories</a></li>
                <li><a href="c-102-consumables.aspx">Consumables</a></li>
                <li><a href="c-100-products.aspx">Products</a></li>
            </ul>

CSS

#accordion {
    list-style: none;
    padding: 0 0 0 0;
    width: 170px;
}
#accordion div {
    background-color:grey;
    background-repeat: no-repeat;
    /*border-radius: 10px 10px 10px 10px;*/
    cursor: pointer;
    display: block;
    font-weight: bold;
    height: 48px;
    list-style: circle outside none;
    margin: 1px;
    width: 230px;
}
#accordion ul {
    list-style: none;
    padding: 0 0 0 0;
}
#accordion ul{
    display: none;
}
#accordion ul li {
    font-weight: normal;
    cursor: auto;
    background-color: #fff;
    padding: 0 0 0 7px;
}
#accordion a {
    text-decoration: none;
}
#accordion a:hover {
    text-decoration: underline;
}
/*new menu css*/

.tameHoriz, ul.tameHoriz li
{
    margin: 0;
    padding: 0;
    list-style: none;
    font-size: 1em;
}
ul.tameHoriz li
{
    display: inline;
    font-size: 1em;
}
br.cl
{
    clear: both;
}

JavaScript

jQuery(document).ready(function() {
    $('#accordion > li > div').hover(function() {
        $(this).next().toggle('slow');
        return false;
    }).next().hide();
});