@keyframes wave {
    0% { transform: rotate(0deg); }
    25% { transform: rotate(14deg); }
    50% { transform: rotate(-8deg); }
    75% { transform: rotate(14deg); }
    100% { transform: rotate(0deg); }
}

#wave-poke-form button:hover {
    animation: wave 0.6s ease-in-out;
}