.float-nav {
    position: fixed;
    top: 50%;
    right: 10px;
    z-index: 10;
}
.float-nav .item {
    height: 44px;
    width: 44px;
    margin-bottom: 2px;
    cursor: pointer;
}
.float-nav .item.kefu {
    background-image: url('/assets/pc2018/images/index/kefu.png');
}
.float-nav .item.kefu:hover {
    background-image: url('/assets/pc2018/images/index/kefu_xuanzhong.png');
}
.float-nav .item.download {
    background-image: url('/assets/pc2018/images/index/APPxiazai.png');
}
.float-nav .item.download:hover {
    background-image: url('/assets/pc2018/images/index/APPxiazai_xuanzhong.png');
}
.float-nav .item.help {
    background-image: url('/assets/pc2018/images/index/bangzhuzhongxin.png');
}
.float-nav .item.help:hover {
    background-image: url('/assets/pc2018/images/index/bangzhuzhongxin_xuanzhong.png');
}
.float-nav .item.calc {
    background-image: url('/assets/pc2018/images/index/lilvjisuan.png');
}
.float-nav .item.calc:hover {
    background-image: url('/assets/pc2018/images/index/lilvjisuan_xuanzhong.png');
}
.float-nav .item.top {
    background-image: url('/assets/pc2018/images/index/backtop.png');
}
.float-nav .item.top:hover {
    background-image: url('/assets/pc2018/images/index/backtop_xuanzhong.png');
}