title: CSS: prevent background from scrolling
body: <p>I have created a modal popup box. I want the background body to be fixed while scrolling. I googled and found to add <code>background-attachment: fixed;</code> but with no success.</p>
  <p>Does background-attachment: fixed; only works for images? as stated in (w3schools.com/cssref/pr_background-attachment.asp)</p>
  <blockquote>
  <p>/* Set background image to fixed (don't scroll along with the page)*/</p>
  </blockquote>
  <pre><code>background-attachment: fixed;
  </code></pre>