JSFiddle - React, Tailwind, and code Playground

HTML

<div id="tab1" onclick="setToActive(this, 'tab2');">
Option 1
</div>

<div id="tab2" onclick="setToActive(this, 'tab1');">
Option 2
</div>

CSS

.active{
     background-color:red;   
}
.inactive{
     background-color:blue;   
}

JavaScript

function setToActive(me, otherId){
    
    me.className='active';
    document.getElementById(otherId).className='inactive';
}