Voozclub

Background
Voozclub (also known as Vooz Character System or simply Vooz) is a South Korean company founded in 2000.

(September 18, 2006-October 31, 2019?)
Logo: On a shade-shifting purple background that's also used in the credits, We see the word "VOOZ" with the word "CHARACTER SYSTEM" below it.

Technique: The text appearing and the background's shade changing.

Music/Sounds: The credits theme.

Availability: It was first seen on Pucca, which premiered in 2006.