Fixed some coloring issues, respect color theme on file-viewer background, make file-viewer images rotatable

lib/theming/darkAppTheme.dart

@@ -10,10 +10,10 @@ class DarkAppTheme {
     colorScheme: const ColorScheme(
       brightness: Brightness.dark,
 
-      surface: Colors.black,
+      surface: Colors.black54,
       onSurface: Colors.white,
 
-      primary: Colors.white,
+      primary: marianumRed,
       onPrimary: Colors.white,
 
       secondary: Colors.grey,