JSFiddle - React, Tailwind, and code Playground

HTML

<div class="accordion-content">hover</div>

CSS

.accordion-content{
        width:100%;
        height:0px;
        background:yellow;
        transition:height 2s;
        -moz-transition:height 2s; /* Firefox 4 */
        -webkit-transition:height 2s; /* Safari and Chrome */
        -o-transition:height 2s; /* Opera */
}
.accordion-content:hover{
        height:200px;
}