JSFiddle - React, Tailwind, and code Playground

HTML

<div>
  <iframe></iframe>
</div>

CSS

div {
    display: flex;
    align-items: center;
    justify-content: center;
}
.iframe{
  width: 200px;
}
div,
body,
html {
    height: 100%;
    width: 100%;
}
body{
    display: table;
    height:100%;
    width: 100%;
}