JSFiddle - React, Tailwind, and code Playground

HTML

<textarea id="characters">100</textarea>

<div id="upto100">
This is content up to 100 characters
</div>

<div id="upto200">
This is content up to 200 characters
</div>

<div id="upto300">
This is content up to 300 characters
</div>

CSS

div {
    width: 250px;
    height: 60px;
    background-color: black;
    color: white;
    display: none;
}

JavaScript

$(document).ready(function(){
 $('#characters').bind('keyup change', function(){
    var elem = $('#upto' + $(this).val());
    
    if(this.lastElem)
       this.lastElem.fadeOut('slow');
     
    if(elem.length){
       this.lastElem = elem;         
       elem.fadeIn('slow');
    }
});
});