Tutorial Time on Speedy TV - Secret Door

Today's Tutorial Time on Speedy TV challenge was totally new to me -- a Secret Door.  Barbie Dopson wrote the tutorial for this very clever card.  Here's my card:

Here's the inside:

And, when you know the trick, here's inside the secret door:

Be sure to check out Barbie's tutorial and then see what the rest of the team did with it.  If you decide to play along, you might win a free stamp set.