title: Removing the up and down arrows in TextField of Material UI
body: <p>I'm trying to remove the top down arrows in the textfield of Material UI.</p>
  <p>Here is the code:</p>
  <pre><code>const theme = createMuiTheme({
  MuiInput: {
    root: {
      &quot;&amp;::-webkit-outer-spin-button, &amp;::-webkit-inner-spin-button&quot;: {
        &quot;-webkit-appearance&quot;: &quot;none&quot;,
        margin: 0
      }
    }
  }
  })
  </code></pre>
  <p>Where am I going wrong?</p>