swing animation

<style>
@keyframes swing {
20% {transform: rotate(15deg);}
40% {transform: rotate(-10deg);}
60% {transform: rotate(5deg);}
80% {transform: rotate(-5deg);}
100% {transform: rotate(0deg);}
}
#swing {
transform-origin: top center;
animation: swing 1s infinite;
}
</style>

<div id="swing">text</div>