.bat {
    position: absolute;
    width: 80px;
    height: 50px;
    background-image: url('../images/bat.png'); /* 請使用蝙蝠剪影PNG */
    background-size: contain;
    background-repeat: no-repeat;
    pointer-events: none;
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
    will-change: transform, opacity;
    animation: flyAway 1.2s ease-out forwards;
}

/* 蝙蝠飛散動畫（無旋轉） */
@keyframes flyAway {
    0% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 1;
    }
    70% {
        opacity: 1;
    }
    100% {
        transform: translate(
            calc(-50% + (var(--x) * 1px)),
            calc(-50% + (var(--y) * 1px))
        ) scale(0.5);
        opacity: 0;
    }
}