You won't be able to dismiss this by usual means (escape or click button), but you can close it programatically based on user choices or actions.
"I love this idea and can't wait to see what our guests write. The cards are beautiful, exactly what I expected. The writing is very light though, so if you prefer something more bold, order it with darker script. The cards were a bit smaller than I had imagined, but that's not good or bad, just different than I had expected. They really are beautiful!"