@keyframes drum-l {
    0%   { transform: translateY(-1rem) rotate(-5deg); }
    50% { transform: translateY(0rem) rotate(0deg); }
    100% { transform: translateY(-1rem) rotate(-5deg); }
}

@keyframes drum-r {
    0%   { transform: translateY(0rem) rotate(0deg); }
    50% { transform: translateY(-1rem) rotate(5deg); }
    100% { transform: translateY(0rem) rotate(0deg); }
}

#stok-l {
    animation: drum-l 0.35s ease-in-out 0s infinite;
    transform-origin: center;
}

#stok-r {
    animation: drum-r 0.35s ease-in-out 0s infinite;
    transform-origin: center;
}