Subtitle: single-line ellipsis on narrow viewports (≤640px)

static/index.html

@@ -46,7 +46,15 @@
     .btn-primary { font-size: 10px; padding: 6px 10px; }
     .btn-primary .plus { font-size: 13px; margin-right: 4px; }
     .title-row { gap: 10px; }
-    .subtitle { font-size: 12px; }
+    .subtitle {
+      font-size: 12px;
+      /* On narrow viewports the description would otherwise wrap to many
+         lines and dominate the page. Single-line ellipsis is friendlier. */
+      white-space: nowrap;
+      overflow: hidden;
+      text-overflow: ellipsis;
+      max-width: 100%;
+    }
     .chart-wrap { height: 260px; padding: 8px; }
   }