JSFiddle - React, Tailwind, and code Playground

HTML

<div class="placeholder" data-placeholder="my placeholder">
    <input value="My text" />  
</div>

CSS

.placeholder
{
    position: relative;
}

.placeholder::after
{
    position: absolute;
    left: 5px;
    top: 3px;
    content: attr(data-placeholder);
    pointer-events: none;
    opacity: 0.6;
}