JSFiddle - React, Tailwind, and code Playground
HTML
<p>hello how r u </p>
<p class='selected'>hey Amar I am fine </p>
<div id="res1">hello:</div>
<div id="res2">hey:</div>
<div id="res3">hiiiii:</div>
<div id="res4">byeeee:</div>
<script>
$('#res1').append($('p:first').hasClass('selected').toString());
$('#res2').append($('p:last').hasClass('selected').toString());
$('#res3').append($('p').hasClass('selected').toString());
$('#res4').append($('p').hasClass('selected').toString());
</script>
CSS
.selected{
color:blue;
}