问Css圆形按钮边框在单击时加载动画

EN

<button type="button" rel="tooltip"
                            class="btn btn-outline-warning btn-round">
                            <span></span>
                            <i class="material-icons">save</i>
                        </button>
     height: 30px;
        min-width: 30px;
        width: 30px;
    border-radius: 50%;
    font-size: 24px;
    height: 41px;
    min-width: 41px;
    width: 41px;
    padding: 0;
    overflow: hidden;
    position: relative;
    line-height: 41px;
    color: #ff9800;
    background-color: transparent;
    border-color: #ff9800;
    border: 1px solid currentColor
    box-shadow: 0 2px 2px 0 hsla(0,0%,60%,.14),0 3px 1px -2px hsla(0,0%,60%,.2),0 1px 5px 0 hsla(0,0%,60%,.12);
    margin: .3125rem 1px;
    outline: 0;
    transition: box-shadow .2s cubic-bezier(.4,0,1,1),background-color .2s cubic-bezier(.4,0,.2,1);
    will-change: box-shadow,transform;