title: How to avoid render-blocking css via scroll-down media query
body: <p>I have a CSS file called lightbox.css on my website that I link to via my header.
  I would like to avoid render-blocking and have looked up media queries as a method  - however, what I would like is to ensure that the CSS loads once the user scrolls down (but after page load). That way I assume it will not be render-blocking, while at the same time it will be available for the parts of the website where it is needed.</p>
  
  <p>Is this possible?</p>