JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
    <li id = 'product_types'><a href='#'>First</a></li>
    <li id = 'product_types'><a href='#'>Second</a></li>
</ul>

CSS

#product_types  {
    background-color: #B0B0B0;
    position: relative;
}

#product_types a:focus 
{     background-color:yellow;    }