PreferenceScreen: fix system bar paddings and nav bar color

ui/src/main/java/de/mm20/launcher2/ui/component/preferences/PreferenceScreen.kt

@@ -1,5 +1,6 @@
 package de.mm20.launcher2.ui.component.preferences
 
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.lazy.LazyColumn
@@ -9,7 +10,8 @@ import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.rounded.ArrowBack
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
-import com.google.accompanist.insets.statusBarsPadding
+import androidx.compose.ui.graphics.Color
+import com.google.accompanist.insets.systemBarsPadding
 import com.google.accompanist.systemuicontroller.rememberSystemUiController
 import de.mm20.launcher2.ui.locals.LocalNavController
 
@@ -21,6 +23,10 @@ fun PreferenceScreen(
     val navController = LocalNavController.current
     val systemUiController = rememberSystemUiController()
     systemUiController.setStatusBarColor(MaterialTheme.colors.surface)
+    systemUiController.setNavigationBarColor(Color.Black)
+    Box(
+        modifier = Modifier.systemBarsPadding()
+    ) {
         Scaffold(
             topBar = {
                 TopAppBar(
@@ -28,7 +34,6 @@ fun PreferenceScreen(
                     title = {
                         Text(title)
                     },
-                modifier = Modifier.statusBarsPadding(),
                     navigationIcon = {
                         IconButton(onClick = {
                             navController?.navigateUp()
@@ -45,4 +50,6 @@ fun PreferenceScreen(
                 content = content
             )
         }
+    }
+
 }