title: Change paper color Material-UI
body: <p>I'm developing a React project using the material-ui library. I'm currently trying to add a drawer which is working fine for me. However, I'm trying to change the background color of this drawer. I've heard that the way to do this is by changing the color of the drawer's paper. I've tried adding the following tag to my CSS object:</p>
  
  <pre><code>const styles = theme =&gt; ({
      background:"BLUE"
  </code></pre>
  
  <p>Then I reference this object in my render function using the classNames library:</p>
  
  <pre><code>  render(){
          const { classes } = this.props;
          return(
      &lt;div className={styles.root}&gt;
      &lt;CssBaseline /&gt;
      &lt;Drawer 
      variant="permanent" 
      className={classNames(classes.drawer, {
          [classes.drawerOpen]: this.state.open,
          [classes.drawerClose]: !this.state.open
      })}
      classes = {{
          paper: classNames({
              background:classes.background,
              [classes.drawerOpen]: this.state.open,
              [classes.drawerClose]: !this.state.open
          })
      }}
  </code></pre>
  
  <p>However, when I run this on localhost, the paper is still a plain old white. Am I missing something about the classNames library or is a special case of the paper tag? Thanks in advance and let me know if I should supply more info than this.</p>