JSFiddle - React, Tailwind, and code Playground

HTML

<div id="nav">
      <table id="navTable" cellspacing="0" cellpadding="0">
        <tr>
            <td><a href="Knowledge">Knowledge</a></td>
            <td class="selected"><a href="Enquiries">Enquiries</a></td>
            <td><a href="Contact">Contact</a></td>
        </tr>
      </table>
    </div>

CSS

div#nav { background: #eee; color: #000; }

div#nav a {
   border-left: 10px  green;

    display: block;
    padding: 20px;
}

div#nav td.selected a{
    background: #ccc;
    color: #004466; }

div#nav td:first-child a, div#nav td.selected a, div#nav td.selected + td a {
   border-left: none;
}