JSFiddle - React, Tailwind, and code Playground

HTML

<input placeholder="Enter Text..." />    

<input readonly value="Read Only" />

<input readonly="readonly" value="Read Only" />

CSS

body{background:#fff}

input
{
    background-color:#fff;
    display:block;
    margin:10px;
    padding:8px 6px;
    width:400px;
}
input[readonly]
{
    background-color:#ccc;
    font-style:italic;
}