Use cardBackgroundColor instead of android:Background (#339)

app/src/main/res/values/styles.xml

@@ -141,10 +141,10 @@
         <item name="layout_behavior">eu.kanade.tachiyomi.widget.FABAnimationUpDown</item>
     </style>
 
-    <style name="Theme.Widget.CardView">
+    <style name="Theme.Widget.CardView" parent="CardView">
         <item name="android:layout_width">match_parent</item>
         <item name="android:layout_height">wrap_content</item>
-        <item name="android:background">?attr/background_card</item>
+        <item name="cardBackgroundColor">?attr/background_card</item>
         <item name="android:layout_marginLeft">@dimen/card_margin</item>
         <item name="android:layout_marginRight">@dimen/card_margin</item>
         <item name="android:layout_marginTop">@dimen/card_margin</item>