title: Bootstrap - .container-fluid inside .container-fluid
body: <p>In bootstrap 5, when I do:</p>
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;html&gt;
  
  &lt;head&gt;
    &lt;link href="https://cdn.jsdelivr.net/npm/bootstrap@5.2.0/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-gH2yIJqKdNHPEq0n4Mqa/HGKIhSkIHeL5AyhkYV8i59U5AR6csBvApHHNl/vI1Bx" crossorigin="anonymous"&gt;
  &lt;/head&gt;
  
  &lt;body&gt;
    &lt;div class="container-fluid" style="background-color: lime;"&gt;
      &lt;div class="container-fluid" style="background-color: red;"&gt;
         &lt;h1&gt;Hello!&lt;/h1&gt;
      &lt;/div&gt;
    &lt;/div&gt;
  &lt;/body&gt;
  &lt;/html&gt;</code></pre>
  </div>
  </div>
  </p>
  <p>the second container is not 100% width.</p>
  <p>I can read the following in the <a href="https://getbootstrap.com/docs/5.0/layout/containers/#how-they-work" rel="nofollow noreferrer">official docs</a>:</p>
  <blockquote>
  <p>.container-fluid, which is width: 100% at all breakpoints</p>
  </blockquote>
  <p>So... why does this happen?</p>