JSFiddle - React, Tailwind, and code Playground

HTML

<body>
    <p>asndklnasj naklsjd klajsdklj askldjklasjdklasj jsakldjaskldj asjd askdjskajdasjdkasjdksajdksadsad aasdj sdsjksdjs  sajksd sjka djsaksjd askdj sadj a</p>
    <div class="bottom">
        Abajo
    </div>
</body>

CSS

.bottom
{
    height:40px;
    width:50%;
    background:red;
    position:fixed;
    bottom:0;
    left:25%;
    -moz-transition:all 1s;
    cursor:pointer;
}
.bottom.click
{
    height:80%;
}

JavaScript

$(".bottom").click(function(){$(this).toggleClass('click')});