Any Color Retro Music Cassette Tape Birthday Greeting Card. All of the text to the front and inside of this funny birthday card can be fully customized, great to add the recipient's name to the front label!!! The color of the cassette tape can be changed on each "page" of the card by selecting the "customize it" option then picking a background color. The super clever design template allows that background color to show through in just the right places at just the right shades!!