JSFiddle - React, Tailwind, and code Playground

HTML

<ul class="dropdownmenulist">
    <li><a href="#">What we do</a>

        <ul>
            <li> <a href="/blah">Web design & development</a>

            </li>
            <li> <a href="/blah">Web hosting</a>

            </li>
            <li> <a href="/blah">Branding</a>

            </li>
            <li> <a href="/blah">Digital Marketing</a>

            </li>
            <li>
<a href="/blah">Software Development</a>

            </li>
        </ul>
    </li>
    
    <li><a href="#">What we do</a>

        <ul>
            <li> <a href="/blah">Web design & development</a>

            </li>
            <li> <a href="/blah">Web hosting</a>

            </li>
            <li> <a href="/blah">Branding</a>

            </li>
            <li> <a href="/blah">Digital Marketing</a>

            </li>
            <li>
<a href="/blah">Software Development</a>

            </li>
        </ul>
    </li>
</ul>

CSS

ul.dropdownmenulist {
    list-style: none;
    margin:0;
    padding:0;
}
ul.dropdownmenulist > li {
    float: left;
    margin: 5px;
    position: relative;
}
ul.dropdownmenulist > li > ul {
    display: none;
    position: absolute;
    background-color: lightgray;
    box-shadow: rgba(0,0,0,0.3) 2px 2px 2px;
}

ul.dropdownmenulist > li:hover > ul {
    display: block;
}