JSFiddle - React, Tailwind, and code Playground

HTML

<nav>
<a>afsa</a>
</nav>

CSS

.current {
    color: red;
}

JavaScript

var childNodes = document.getElementsByTagName('nav')[0].childNodes;
for (var i = 0; i < childNodes.length; i++) {
    console.log(childNodes[i].nodeType);
    if (childNodes[i].nodeType !== 3) {
      childNodes[i].className = "current";
    }        
}