fix pop, fix gradient background looking bad

lib/ui/fancy_scaffold.dart

@@ -74,7 +74,7 @@ class FancyScaffoldState extends State<FancyScaffold>
     return ValueListenableBuilder(
       valueListenable: statusNotifier,
       builder: (context, state, child) => PopScope(
-          canPop: state != AnimationStatus.dismissed,
+          canPop: state == AnimationStatus.dismissed,
           onPopInvoked: state == AnimationStatus.dismissed
               ? null
               : (_) => dragController.fling(velocity: -1.0),

lib/ui/player_screen.dart

@@ -195,7 +195,8 @@ class PlayerScreenBackground extends StatelessWidget {
                       end: Alignment.bottomCenter,
                       colors: [
                         if (provider.dominantColor != null)
-                          provider.dominantColor!,
+                          Color.lerp(provider.dominantColor,
+                              isLightMode ? Colors.white : Colors.black, 0.5)!,
                         Theme.of(context).scaffoldBackgroundColor,
                       ],
                       stops: const [0.0, 0.6],