button.css

@keyframes wave{
    20% {
        transform: scale(0.2);
        opacity: 0.8;
    }
    40% {
        transform: scale(0.4);
        opacity: 0.6;
    }
    60% {
        transform: scale(0.6);
        opacity: 0.4;
    }
    80% {
        transform: scale(0.8);
        opacity: 0.2;
    }
    100% {
        transform: scale(1);
        opacity: 0;
    }
}
.button {
  overflow: hidden;
  position: relative;
  border:2px solid #fff;
  background:#2894FF;
  border-radius: 10px;
  width: 200px;
  height: 50px;
}

.wave {
    border-radius: 50%;
    position: absolute;
    top:50%;
    margin-top: -200px;
    left: 50%;
    margin-left: -200px;
    background: #fff;
    width: 400px;
    height: 400px;
    transform: scale(0.01);
    opacity: 0;
}
/* 悬浮替代点击 */
.button:hover .wave{
  animation: wave linear 1s;
}