JSFiddle - React, Tailwind, and code Playground
by sonylnagale
HTML
<h1 id="title">My Form</h1>
Name: <input type="text" id="name" />
<button id="submit">Submit</button>
CSS
.error {
border: 1px solid red;
}
JavaScript
document.getElementById('submit').onclick = function(event) {
if (document.getElementById('name').value === '') {
document.getElementById('name').classList = "error"
} else {
document.getElementById('name').classList = ""
}
}