JSFiddle - React, Tailwind, and code Playground

HTML

<form>
    <input type="email" placeholder="enter email" name="q" required="">
    <input type="submit" value="Go">
</form>

CSS

input {
    border:solid 1px blue;
    box-shadow:none;
}

input:-moz-placeholder {
    box-shadow:none !important;
}

input:invalid {
    box-shadow:0 0 3px lime;
}