        }
        .smallImg {
            filter: blur(15px);
            -webkit-filter: blur(15px);
            position: absolute;
            top: 0;
            left: 0;
            height: 100%;
            width: 100%;
            background-image: url("https://cn.bing.com/th?id=OHR.BryceSnow_EN-US1471442313_UHD.jpg&pid=hp&w=480"); /* 使用小图 */
            background-position: center;
            background-repeat: no-repeat;
            background-size: cover;
            transition: opacity 2