activity_3.xml

<?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="#ECF0F3"
    tools:context="com.github.sshadkany.android_neumorphic_test_app.Activity3">

    <com.github.sshadkany.shapes.RoundRectView
        android:id="@+id/btn3"
        android:layout_width="350dp"
        android:layout_height="500dp"
        android:layout_margin="5dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:shape_roundRect_backgroundColor="#0591FA"
        app:shape_roundRect_bottomLeftRadius="12dp"
        app:shape_roundRect_bottomRightRadius="12dp"
        app:shape_roundRect_shadow_type="drop_shadow"
        app:shape_roundRect_topLeftRadius="12dp"
        app:shape_roundRect_topRightRadius="12dp">

        <com.github.sshadkany.shapes.RoundRectView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_margin="5dp"
            app:shape_roundRect_backgroundColor="#ECF0F3"
            app:shape_roundRect_bottomLeftRadius="12dp"
            app:shape_roundRect_bottomRightRadius="12dp"
            app:shape_roundRect_shadow_type="small_inner_shadow"
            app:shape_roundRect_topLeftRadius="12dp"
            app:shape_roundRect_topRightRadius="12dp">

            <com.github.sshadkany.shapes.RoundRectView
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_margin="15dp"
                app:shape_roundRect_backgroundColor="#ECF0F3"
                app:shape_roundRect_bottomLeftRadius="12dp"
                app:shape_roundRect_bottomRightRadius="12dp"
                app:shape_roundRect_shadow_type="drop_shadow"
                app:shape_roundRect_topLeftRadius="12dp"
                app:shape_roundRect_topRightRadius="12dp">

            </com.github.sshadkany.shapes.RoundRectView>
        </com.github.sshadkany.shapes.RoundRectView>
    </com.github.sshadkany.shapes.RoundRectView>

</androidx.constraintlayout.widget.ConstraintLayout>