import React from "react";
import ReactDOM from "react-dom";

import Grid from "@material-ui/core/Grid";
import Box from "@material-ui/core/Box";
import { makeStyles } from "@material-ui/core/styles";

const useStyles = makeStyles({
  gridItem: {
    border: "1px solid red"
  }
});

function App() {
  const classes = useStyles();
  return (
    
      
        XX
      
      
        YY
      
      
        ZZ
      
    
  );
}

const rootElement = document.getElementById("root");
ReactDOM.render(, rootElement);