/*** アニメーションの定義 ***/
@keyframes textWave {
 0% {
 top: 0;
 }
 100% {
 top: -0.3em;
 }
}

.wave span {
display: inline-block;
position: relative;
}
.wave span {
animation-name: textWave;
animation-duration: 0.5s;
animation-timing-function: ease-in-out;
animation-iteration-count: infinite;
animation-direction: alternate;
}
.wave span:nth-of-type(2) {
animation-delay: 0.125s;
}
.wave span:nth-of-type(3) {
animation-delay: 0.25s;
}