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.
"This card had a good contrast to the invitation with the golden dots. They helped make everything sound the same as the invitation while keeping it short and sweet. Again, simple elegance!"
"Got the designer to completely change the format, add a place for email addresses, and delete the dreded M that signafies where we all know to add our name... except when you're name starts with Dr. or Rev. She helped turn this old style response card (with a beautiful design) into a modern looking RSVP ! I Absolutely love it!"