app/src/main/res/drawable-hdpi/navigation_item_selected_bg_dark.xml
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:bottom="3dp"
android:right="20dp"
android:top="3dp">
<shape android:shape="rectangle">
<solid android:color="#2FFFFFFF" />
<corners
android:bottomRightRadius="40dp"
android:topRightRadius="40dp" />
</shape>
</item>
</layer-list>