Mobile combing: WOTD watermark, Entertainment card breathing, Art lightbox fit

- WOTD /word: watermark was nudged too far down last round; bring it back up to
  sit JUST below the date (clears it by a few px instead of dropping markedly).
- home3 Entertainment card: stacked on mobile it lost the height it borrowed from
  Play on desktop and felt crowded — add vertical breathing (padding + gaps), not
  as tall as desktop.
- /art lightbox: on a narrow portrait phone the framed piece (image + mat + rail)
  overflowed the viewport (rail clipped → looked distorted). Cap the image so the
  WHOLE frame fits, leaving room for the caption.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/routes/art/+page.svelte

@@ -405,4 +405,13 @@
   .lb-frame.frame--none img { max-width: 96vw; max-height: 88vh; }   /* no frame → go big */
   .lb-cap { color: #5b636e; font-size: 0.9rem; }
   .lb-cap .sep { color: #a6acb4; }
+
+  /* On a narrow portrait phone the framed piece (image + mat + rail) overflowed the
+     viewport — the rail got clipped and the whole thing read as distorted. Pull the
+     image cap in so the WHOLE frame fits on screen, and leave room for the caption. */
+  @media (max-width: 640px) {
+    .lb-frame { max-width: 94vw; }
+    .lb-frame img { max-width: 72vw; max-height: 60vh; }
+    .lb-frame.frame--none img { max-width: 92vw; max-height: 78vh; }
+  }
 </style>