title: how to add style (add bottom border )in all li in react?
body: <p>I a using react material components <code>List</code> which  internally is <code>ul li</code>.I want to add style in all <code>li</code> (add bottom border) .one way is to add this <code>className={classes.sideBar__listItem__element}
  </code>in all <code>ListItem</code>  is there any better way to do this any way to do nesting ?</p>
  
  <p><a href="https://codesandbox.io/s/1yr3nlqp74" rel="nofollow noreferrer">https://codesandbox.io/s/1yr3nlqp74</a></p>
  
  <pre><code>import React, { Fragment } from "react";
  import { Paper, ListItem, List, ListItemText } from "@material-ui/core";
  import { withStyles } from "@material-ui/core/styles";
  
  const styles = {
    sideBar__block: {
      padding: 20
    },
    sideBar__list__element: {
      li: {
        borderBottom: "1px solid rgb(212, 212, 212)"
      }
    },
  
    sideBar__listItem__element: {
      borderBottom: "1px solid rgb(212, 212, 212)"
    }
  };
  const SideBar = props =&gt; {
    const { classes } = props;
    return (
      &lt;div className={classes.sideBar__block}&gt;
        &lt;Paper className={classes.sideBar__list__element}&gt;
          &lt;List&gt;
            &lt;ListItem className={classes.sideBar__listItem__element}&gt;
              &lt;ListItemText primary="form" secondary=" FORM" /&gt;
            &lt;/ListItem&gt;
            &lt;ListItem&gt;
              &lt;ListItemText primary="E" secondary=" Inbox" /&gt;
            &lt;/ListItem&gt;
            &lt;ListItem&gt;
              &lt;ListItemText primary="re box" secondary=" Inbox" /&gt;
            &lt;/ListItem&gt;
            &lt;ListItem&gt;
              &lt;ListItemText primary="Upload" secondary="upload" /&gt;
            &lt;/ListItem&gt;
          &lt;/List&gt;
        &lt;/Paper&gt;
      &lt;/div&gt;
    );
  };
  
  export default withStyles(styles)(SideBar);
  </code></pre>
  
  <p>I am using this example
  <a href="https://material-ui.com/demos/lists/" rel="nofollow noreferrer">https://material-ui.com/demos/lists/</a></p>