update list_item_system_message.xml

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

@@ -5,7 +5,6 @@
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:orientation="vertical"
-    android:background="@android:color/white"
     android:theme="@style/AppTheme">
 
     <include layout="@layout/list_item_message_newday" />