Change NewsFragment design to match app theme

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

 <?xml version="1.0" encoding="utf-8"?>
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:layout_marginBottom="4dp"
     android:layout_marginLeft="8dp"
     android:layout_marginRight="8dp"
     android:layout_marginTop="4dp"
-    android:background="#f2f2f2">
+    app:cardCornerRadius="1dp"
+    app:cardElevation="1dp">
 
     <LinearLayout
         android:layout_width="match_parent"
@@ -58,4 +60,4 @@
             android:textColor="#000000"
             android:textColorLink="@color/colorPrimary" />
     </LinearLayout>
-</LinearLayout>
+</android.support.v7.widget.CardView>