diff --git a/app/src/main/java/it/niedermann/owncloud/notes/android/fragment/AccountChooserDialogFragment.java b/app/src/main/java/it/niedermann/owncloud/notes/android/fragment/AccountChooserDialogFragment.java
index c996970e..787a2cff 100644
--- a/app/src/main/java/it/niedermann/owncloud/notes/android/fragment/AccountChooserDialogFragment.java
+++ b/app/src/main/java/it/niedermann/owncloud/notes/android/fragment/AccountChooserDialogFragment.java
@@ -57,7 +57,7 @@ public class AccountChooserDialogFragment extends AppCompatDialogFragment implem
         RecyclerView.Adapter adapter = new AccountChooserAdapter(accountsList, this, getActivity());
         accountRecyclerView.setAdapter(adapter);
 
-        return new AlertDialog.Builder(getActivity(), R.style.ncAlertDialog)
+        return new AlertDialog.Builder(getActivity())
                 .setView(view)
                 .setTitle(R.string.simple_move)
                 .setNegativeButton(android.R.string.cancel, null)
diff --git a/app/src/main/java/it/niedermann/owncloud/notes/android/fragment/CategoryDialogFragment.java b/app/src/main/java/it/niedermann/owncloud/notes/android/fragment/CategoryDialogFragment.java
index 258699da..43240a76 100644
--- a/app/src/main/java/it/niedermann/owncloud/notes/android/fragment/CategoryDialogFragment.java
+++ b/app/src/main/java/it/niedermann/owncloud/notes/android/fragment/CategoryDialogFragment.java
@@ -137,7 +137,7 @@ public class CategoryDialogFragment extends AppCompatDialogFragment {
             }
         });
 
-        return new AlertDialog.Builder(getActivity(), R.style.ncAlertDialog)
+        return new AlertDialog.Builder(getActivity())
                 .setTitle(R.string.change_category_title)
                 .setView(dialogView)
                 .setCancelable(true)
diff --git a/app/src/main/java/it/niedermann/owncloud/notes/persistence/NoteServerSyncHelper.java b/app/src/main/java/it/niedermann/owncloud/notes/persistence/NoteServerSyncHelper.java
index 932aab9b..a9ca6fcf 100644
--- a/app/src/main/java/it/niedermann/owncloud/notes/persistence/NoteServerSyncHelper.java
+++ b/app/src/main/java/it/niedermann/owncloud/notes/persistence/NoteServerSyncHelper.java
@@ -1,6 +1,5 @@
 package it.niedermann.owncloud.notes.persistence;
 
-import android.app.Activity;
 import android.content.BroadcastReceiver;
 import android.content.ClipData;
 import android.content.ClipboardManager;
@@ -17,6 +16,7 @@ import android.view.View;
 import android.widget.Toast;
 
 import androidx.appcompat.app.AlertDialog;
+import androidx.appcompat.app.AppCompatActivity;
 
 import com.google.android.material.snackbar.Snackbar;
 import com.nextcloud.android.sso.exceptions.NextcloudApiNotRespondingException;
@@ -427,11 +427,11 @@ public class NoteServerSyncHelper {
                     Log.e(TAG, e.getMessage(), e);
                 }
                 String statusMessage = context.getApplicationContext().getString(R.string.error_sync, context.getApplicationContext().getString(status.str));
-                if (context instanceof ViewProvider && context instanceof Activity) {
+                if (context instanceof ViewProvider && context instanceof AppCompatActivity) {
                     Snackbar.make(((ViewProvider) context).getView(), statusMessage, Snackbar.LENGTH_LONG)
                             .setAction(R.string.simple_more, v -> {
-                                String debugInfos = ExceptionUtil.getDebugInfos((Activity) context, exceptions);
-                                new AlertDialog.Builder(context, R.style.ncAlertDialog)
+                                String debugInfos = ExceptionUtil.getDebugInfos((AppCompatActivity) context, exceptions);
+                                new AlertDialog.Builder(context)
                                         .setTitle(statusMessage)
                                         .setMessage(debugInfos)
                                         .setPositiveButton(android.R.string.copy, (a, b) -> {
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
index 7c1ba746..b1298909 100644
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -19,11 +19,11 @@
 
     <color name="icon_color_default">#757575</color>
 
-    <color name="widget_background">#DFFFFFFF</color>
+    <color name="widget_background">#dfffffff</color>
     <color name="widget_fg_default">#000000</color>
     <color name="widget_fg_contrast">#ffffff</color>
 
-    <color name="category_background">#FFF</color>
+    <color name="category_background">#ffffff</color>
     <color name="category_border">@color/primary</color>
 
     <!-- Dark Theme -->
diff --git a/app/src/main/res/values/styles.xml b/app/src/main/res/values/styles.xml
index 70516c53..e030cd19 100644
--- a/app/src/main/res/values/styles.xml
+++ b/app/src/main/res/values/styles.xml
@@ -8,20 +8,11 @@
         <item name="windowActionModeOverlay">true</item>
     </style>
 
-    <style name="ncAlertDialog" parent="@style/Theme.AppCompat.DayNight.Dialog.Alert">
-        <item name="colorAccent">@color/primary</item>
-        <item name="colorPrimary">@color/primary</item>
-        <item name="colorPrimaryDark">@color/primary</item>
-        <item name="android:windowBackground">@color/bg_normal</item>
-    </style>
-
     <style name="fab">
         <item name="android:layout_margin">16dp</item>
         <item name="android:layout_width">wrap_content</item>
         <item name="android:layout_height">wrap_content</item>
         <item name="android:layout_gravity">end|bottom</item>
-        <item name="android:layout_alignParentBottom">true</item>
-        <item name="android:layout_alignParentRight">true</item>
     </style>
 
     <style name="SplashTheme" parent="AppTheme">