JSFiddle - React, Tailwind, and code Playground

by slace

HTML

<nav>
    <ol>
        <li>One
            <ol>
                <li>One dot one</li>
            </ol>
        </li>
        <li>Two</li>
    </ol>
</nav>

CSS

ol > li {
    float: left;
    width: 100px;
    padding: 5px;
}

ol > li ol {
    visibility:hidden;
}

ol > li:hover ol {
    display: block;
    visibility: visible;
}