JSFiddle - React, Tailwind, and code Playground

CSS

body {
    font-family:"b nazanin", "b roya", times new roman;
    font-size:16px;
    outline:10px solid white;
    margin:0 auto;
    min-width:948px;
    min-height:550px;
    width:100%;
    height:100%;
}
html {
    background: fixed -webkit-linear-gradient(red, blue);
    background: fixed -o-linear-gradient(red, blue);
    background: fixed -moz-linear-gradient(red, blue);
    background: fixed -webkit-linear-gradient(red, blue);
    background: fixed linear-gradient(red, blue);
}