Sabrina: The Animated Series (1999)

S1E11 Shrink to Fit

Gem proudly shows off her new Waif Moif jeans, but initially, Sabrina and Chloe aren't impressed. However, when Harvey admires them, the friends change their tune. They struggle to fit into the jeans, but in a bid to solve their problem, they cast a shrinking spell. Instead of shedding a few pounds, they end up losing several inches!