Fixed: Change extra keys and terminal input view background to black

Required for day/night theming and should fix issues where both views were translucent with light terminal color themes.

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

@@ -100,7 +100,7 @@
             android:visibility="gone"
             android:layout_width="match_parent"
             android:layout_height="37.5dp"
-            android:background="@android:drawable/screen_background_dark_transparent"
+            android:background="@color/black"
             android:layout_alignParentBottom="true" />
 
     </RelativeLayout>