text: import React from 'react';
  import { Link as RouterLink } from 'react-router-dom';
  import clsx from 'clsx';
  import PropTypes from 'prop-types';
  import { makeStyles } from '@material-ui/styles';
  import { AppBar, Toolbar } from '@material-ui/core';
  
  const useStyles = makeStyles(() => ({
    root: {
      boxShadow: 'none'
    }
  }));
  
  const Topbar = props => {
    const { className, ...rest } = props;
  
    const classes = useStyles();
  
    return (
      <AppBar
        {...rest}
        className={clsx(classes.root, className)}
        color="primary"
        position="fixed">
        <Toolbar>
          <RouterLink to="/">
            <img alt="Logo" src="/images/logos/logo--white.svg" />
          </RouterLink>
        </Toolbar>
      </AppBar>
    );
  };
  
  Topbar.propTypes = {
    className: PropTypes.string
  };
  
  export default Topbar;
  