.wiggle {
    animation: wiggle 0.5s;
    animation-iteration-count: infinite;
}

@keyframes wiggle {
    0% {transform: rotate(0deg);}
    15% {transform: rotate(3deg);}
    30% {transform: rotate(0deg);}
    45% {transform: rotate(3deg);}
    60% {transform: rotate(0deg);}
    80% {transform: rotate(3deg);}
    100% {transform: rotate(0deg);}
}