/*定义的一个提示框*/
.text-tip {
    display: block;
    background:rgba(0,0,0,.7);
    color: #fff;
    padding: 10px 10px;
    line-height: 18px;
    position: fixed;
    left: 50%;
    bottom: 25%;
    -webkit-transform: translate(-50%);
    transform: translate(-50%);
    border-radius: 3px;
    display: none;
    z-index: 9999;
    font-size: 12px;
    text-align: center;
}