title: React withStyles throws error when using 'direction'
body: <p>I have a simple React website and am using the withStyles feature to pass styles to a material-ui Grid element. When trying to use <code>direction: "column"</code> in the style, I get the error message included below.</p>
  
  <p>This is in a .jsx file. I have found a fix by specifying type, but that only works for TypeScript.</p>
  
  <p>Here is the App.jsx file:</p>
  
  <pre><code>
  const styles = theme =&gt; ({
      root: {
          direction: "column",
          justify: "center",
          alignItems: "center",
      },
  });
  
  function App(props) {
  
      return (
          &lt;div&gt;
              &lt;Grid container className={props.classes.root} &gt;
                  &lt;Typography variant="h2"&gt;
                      Test Website
                  &lt;/Typography&gt;
                  &lt;TextField
                      id="input-user"
                      label="User"
                      value={1}
                      margin="normal"
                      variant="outlined"
                  /&gt;
  
              &lt;/Grid&gt;
          &lt;/div&gt;
      )
  
  }
  
  export default withStyles(styles)(App);
  </code></pre>
  
  <p>The error message I am getting is this:</p>
  
  <pre><code>Argument of type '(theme: any) =&gt; { root: { direction: string; justify: string; alignItems: string; }; }' is not assignable to parameter of type 'Styles&lt;Theme, {}, "root"&gt;'.
    Type '(theme: any) =&gt; { root: { direction: string; justify: string; alignItems: string; }; }' is not assignable to type 'StyleRulesCallback&lt;Theme, {}, "root"&gt;'.
      Type '{ root: { direction: string; justify: string; alignItems: string; }; }' is not assignable to type 'Record&lt;"root", CreateCSSProperties&lt;{}&gt; | ((props: {}) =&gt; CreateCSSProperties&lt;{}&gt;)&gt;'.
        Types of property 'root' are incompatible.
          Type '{ direction: string; justify: string; alignItems: string; }' is not assignable to type 'CreateCSSProperties&lt;{}&gt; | ((props: {}) =&gt; CreateCSSProperties&lt;{}&gt;)'.
            Type '{ direction: string; justify: string; alignItems: string; }' is not assignable to type 'CreateCSSProperties&lt;{}&gt;'.
              Types of property 'direction' are incompatible.
                Type 'string' is not assignable to type '"-moz-initial" | "inherit" | "initial" | "revert" | "unset" | "ltr" | "rtl" | ((props: {}) =&gt; DirectionProperty)'.
  </code></pre>
  
  <p>Thank you for any help.</p>