rand < 0.6) {
          star.classList.add('small');
        } else if (rand < 0.8) {
          star.classList.add('medium');
        } else if (rand < 0.95) {
          star.classList.add('large');
        } else {
          star.classList.add('bright');
        }
        
        star.style.left = Math.random() * 100 + '%';
        star.style.top = Math.random() * 100 + '%';
        star.style.animationDelay = Math.random() * 3 + 's';
        star.style.animationDuration = (Math.random() * 3 + 2) + 's';
 