picture showing through text container

I added a picture as a background. Can I now add a text container where the background picture show through vaguely (so a half-transparent text container), so that you can still see the container AND the picture.

Bit difficult to explain. Normally when you add a text container in front of a picture you’ll only see the picture and some text in it. I want to see the container and the background picture in that container vaguely on the back. So that even when the picture is somewhat colourly you can till read the text.

Can you do that in Blurb BookSmart?

Thanks.