I made a responsive version here: https://github.com/sw-yx/spark-joy/blob/master/README.md#lay...

  .swyxcontent {
   --gap: clamp(1rem, 6vw, 3rem);
   --full: minmax(var(--gap), 1fr);
   --content: min(65ch, 100% - var(--gap) * 2);
   --popout: minmax(0, 2rem);
   --feature: minmax(0, 5rem);

   display: grid;
   grid-template-columns: 
    [full-start]
    [feature-start]
    [popout-start]
    [content-start] var(--content) [content-end]
    [feature-end]
    [popout-end]
    [feature-end]
    [full-end]
  }

  @media (min-width: 640px) {
   .swyxcontent {
    grid-template-columns:
     [full-start] var(--full)
     [feature-start] var(--feature)
     [popout-start] var(--popout)
     [content-start] var(--content) [content-end]
     var(--popout) [popout-end]
     var(--feature) [feature-end]
     var(--full) [full-end];
   }
  }