JSFiddle - React, Tailwind, and code Playground

HTML

<div><textarea></textarea></div>

CSS

div {
    border:1px solid silver;
    width:200px;
    height:100px;
    padding:5px;
}

textarea {
    width:190px;
    height:90px;
}

textarea:focus div {
    border:1px solid red;
}