点击元素或按钮出现炫酷波纹

        
ripple
        ripple set
        ripple with very long content


 .ripple {
        position: relative;
        overflow: hidden;  /*隐藏溢出的径向渐变背景 */
    }

.ripple:after {
    content: "";
    display: block;
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    pointer-events: none;
    background-image: radial-gradient(circle, blue 10%, transparent 10.01%); /*设置径向渐变 */
    background-repeat: no-repeat;
    background-position: 50%;
    transform: scale(10, 10);
    opacity: 0;
    transition: transform .3s, opacity .5s;
}

.ripple:active:after {  /*设置初始状态 */
    transform: scale(0, 0);
    opacity: .3;
    transition: 0s;   
}
button{
    height:30px;

}