Transparent image changing color to very light when used on light background in Unity


I’m trying to use this transparent image (transparent brown, with a transparent white shadow):
transparent brown front
over this background:
enter image description here
in Unity UI.

But the end result is not similar to what I see in photoshop at all.

What I expect and what I have inPhotoshop:
enter image description here
What I get in Unity:
enter image description here

How can I fix this?