【7B2主题美化】手机菜单右下角添加客服图片

添加CSS代码，图片自行修改

.mobile-box.show-menu-box:after {
width: 170px;
height: 160px;
position: absolute;
bottom: 0;
right: 0;
content: " ";
background-image: url(https://www.lsenyu.cn/wp-content/themes/b2Jitheme/img/kefu.png);
background-size: 100% 100%;
}