RetroMusicPlayer/app/src/main/res/drawable/ic_expand_less.xml

<vector android:height="24dp"
    android:tint="#FFFFFF"
    android:viewportHeight="24.0"
    android:viewportWidth="24.0"
    android:width="24dp"
    xmlns:android="http://schemas.android.com/apk/res/android">
    <path
        android:fillColor="#FF000000"
        android:pathData="M12,8l-6,6 1.41,1.41L12,10.83l4.59,4.58L18,14z" />
</vector>