            card.style.opacity = 0; card.style.transform = 'translateY(30px)';
                    card.style.transition = 'opacity 0.5s ease, transform 0.5s ease';
                    card.style.transitionDelay = (index * 0.1) + 's';
                    observer.observe(card);
                });
            } else {
                cards.forEach((card, index) => {
                    card.style.opacity = 0; card.style.transform = 'translateY(30px)';
                    card.style.transition = 'opa