Update UI Style

app/src/main/res/layout/dialog_photo_view.xml

@@ -1,8 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
-    android:layout_height="match_parent"
-    android:background="@color/background">
+    android:layout_height="match_parent">
 
     <io.legado.app.ui.widget.image.PhotoView
         android:id="@+id/photo_view"