Android Button background from style does not apply

Question

I am trying to setup style for Button, but from some unknown reasons attribute "background" from style is not applying. I want achieve a transparent rectangle button over arrow that is on lower layer.

I created style ButtonMorse:

<style name="ButtonMorse" parent="Widget.AppCompat.Button">
        <item name="android:layout_width">30dp</item>
        <item name="android:layout_height">30dp</item>
        <item name="background">@color/transparent</item>
        <item name="backgroundColor">@color/transparent</item>
    </style>

For comparison 1st button background attribute is set directly, not using style (works fine).

Layout code:

<Button
        android:id="@+id/buttonUp0"
        android:layout_marginStart="525dp"
        android:layout_marginTop="420dp"
        android:onClick="buttonUp0Click"
        android:layout_width="30dp"
        android:layout_height="30dp"
        android:background="@color/transparent"/>

    <TextView
        style="@style/CharacterMorseTextView"
        android:id="@+id/character0"
        android:layout_marginStart="522dp"
        android:layout_marginTop="450dp" />

    <Button
        style="@style/ButtonMorse"
        android:id="@+id/buttonDown0"
        android:layout_marginStart="525dp"
        android:layout_marginTop="525dp"
        android:onClick="buttonDown0Click"/>

Color: <color name="transparent">#00000000</color>

Result: Result on emulator

Answer 1

As Ananta commented - there was mistake in my style file. It should be:

<item name="android:background">@color/transparent</item>

instead of:

<item name="background">@color/transparent</item>

Question closed.