@media screen and (max-width:768px) {
    .nymain .leftNav>h2 span {
        float: right;
        width: 30px;
        height: 30px;
        margin-top: 8px;
        background: url(images/sub_left_down2.png) no-repeat center center;
        background-position: center center;
        margin-right: 10px;
        transition: all .3s;}
    .container .leftNav>h2 span {
        float: right;
        width: 30px;
        height: 30px;
        margin-top: 8px;
        background: url(images/sub_left_down2.png) no-repeat center center;
        background-position: center center;
        margin-right: 10px;
        transition: all .3s;}