apply custom theme mui code example

Example: use theme in component mui

import React from "react";
import { makeStyles } from "@material-ui/core/styles";

const useStyles = makeStyles((theme) => ({
  root: {
    backgroundColor: theme.palette.secondary.main
  }
}));

export default function App() {
  const classes = useStyles();
  return (
    

      
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  );
}