Drop the app shot on a phone

Stacked, the screenshot took most of a phone screen before any of the words,
and it is a picture of the app on the kind of device the reader is already
holding. It stays on desktop, where it sits beside the copy rather than above
it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

Public/portal.css

@@ -811,7 +811,10 @@ a.platform:hover { background: linear-gradient(180deg, #FFFFFF 0%, #F6F3E9 52%,
 
 @media (max-width: 860px) {
   .hero-inner { flex-wrap: wrap; }
-  .hero-art { order: -1; }
+  /* The app shot goes. Stacked, it took most of a phone screen before
+     any of the words, and it is a picture of the thing the reader is
+     already holding a phone to install. */
+  .hero-art { display: none; }
   .platforms { grid-template-columns: repeat(2, 1fr); }
   .split, .commun { grid-template-columns: 1fr; }
 }