fix(pwa): keep the status bar readable in the light theme

The installed iOS app uses the `black-translucent` status bar, which
always draws white text, and the shell painted the strip behind it in
the card colour. In the light theme that is near-white, so the clock
and battery vanished. The light theme now paints the strip in its dark
ink; the dark theme is unchanged.

src/app/globals.css

@@ -724,6 +724,16 @@ body,
     }
   }
 
+  /*
+   * The installed iOS app runs with `black-translucent` (`layout.tsx`), which
+   * always draws the clock and battery in white. Over the light theme's card
+   * colour they disappear, so the light theme paints the strip in its dark
+   * ink instead.
+   */
+  :root.light .shell-safe-area {
+    background-image: linear-gradient(var(--foreground), var(--foreground));
+  }
+
   /*
    * The on-screen keyboard. iOS Safari, and Chrome on Android by default,
    * shrink only the visual viewport when the keyboard opens: everything