title: How do you toggle filtered list items inside of a div in React?
body: <p>I'm building a React component that shows a filtered list of items in a div when users click on a button. Only the items within that div should be displayed on click. For some reason, though, the lists for <em>every</em> section are being toggled. </p>
  
  <p>What am I doing wrong?</p>
  
  <p>Here is my code: <a href="https://codesandbox.io/s/6yr0jzlpwn" rel="nofollow noreferrer">https://codesandbox.io/s/6yr0jzlpwn</a> </p>