Android Studio – making recycleview item transparent compare to background

So currently I set up the background image of the app main activity page, but the recycleview item is blocking it, is there a way to display my recycleview item without blocking the background image? I have try to add android::background = /transparent before and it did not work

My recycleview item have the following xml layout file:

<?xml version="1.0" encoding="utf-8"?>
  <com.google.android.material.card.MaterialCardView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="8dp"
>

<LinearLayout
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="16dp"
        android:textAppearance="?attr/textAppearanceHeadline6" />


    <TextView
        android:id="@+id/dueDate"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="16dp"
        android:textAppearance="?attr/textAppearanceHeadline6" />

    <TextView
        android:id="@+id/completeDate"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="16dp"
        android:textAppearance="?attr/textAppearanceHeadline6" />

    <CheckBox
        android:id="@+id/checkBox"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Complete" />

</LinearLayout>
 </com.google.android.material.card.MaterialCardView>

And my main activity have the following layout

<?xml version="1.0" encoding="utf-8"?>
 <androidx.constraintlayout.widget.ConstraintLayout 
 xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/background2"
tools:context=".MainActivity">

<androidx.recyclerview.widget.RecyclerView
    android:id="@+id/recyclerview"
    android:layout_width="0dp"
    android:layout_height="0dp"
    tools:listitem="@layout/recyclerview_item"
    android:padding="@dimen/big_padding"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toTopOf="parent" />

<com.google.android.material.floatingactionbutton.FloatingActionButton
    android:id="@+id/fab"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_margin="16dp"
    android:src="@drawable/ic_baseline_add_24dp"/>

 </androidx.constraintlayout.widget.ConstraintLayout>

enter image description here