title: How do I add borderTop to React Material UI Table?
body: <p><a href="https://i.stack.imgur.com/RIViY.png" rel="noreferrer"><img src="https://i.stack.imgur.com/RIViY.png" alt="enter image description here"></a></p>
  
  <p>What I want to do add top-border to above table. </p>
  
  <p>I tried</p>
  
  <pre><code>const styles = theme =&gt; {
      root : { borderTopWidth: 1, borderColor: 'red'}
  }
  
  ...
  
  class TableComponent ...
  
  { classes } = this.props; 
  
  &lt;Table className={classes.root}&gt;
  &lt;/Table
  
  export default withStyles(styles)(TableComponent)
  </code></pre>
  
  <p>I believe it's not a syntax problem, because other option like <code>background: 'red' working properly.</code> Perhaps I missed something. How can I implement topBorder to this table?</p>