title: CSS nth child to select the 3rd element and then every 4th?
body: <p>I'm trying to select the 3rd element, and then every 4.</p>
  
  <p>So it would select 3, 7, 11, 15, 19, 23... etc.</p>
  
  <pre><code>.project:nth-child(3), .project:nth-child(7n+4) {
      margin: 40px 0px 0px 0px;
  }
  </code></pre>
  
  <p>What is wrong with the current code? It's not working, the margin is still set to 40px on the right margin.</p>