improved manifest

Author: manish

client/public/manifest.json

@@ -20,7 +20,7 @@
     ],
     "start_url": ".",
     "display": "standalone",
-    "theme_color": "#000000",
+    "theme_color": "#888888",
     "background_color": "transparent",
     "background_color_media": {
       "media": "(prefers-color-scheme: dark)",