 <style type="text/css">
            body{background-image: url(img/001.jpg);}
            .lb{
                margin: 10px auto;
                width: 1000px;
                height: 250px;
            }
            #you{
                cursor: pointer;
                display: inline-block;
                height: 45px;
                width: 45px;
                left: 950px;
                top: -150px;
                position: relative;
                z-index: 1;
            }
            #zuo{
                cursor: pointer;
                height: 45px;
                width: 45px;
                top: 150px;
                position: relative;
                z-index: 1;
            }
            .f{
              //  opacity:0.2;//设置透明
            }
            .f:hover
            {
                opacity:1.0;//设置鼠标经过不透明
            }
            li{
                list-style-type: square;
                border: 1px #000;
                width: 100px;
                height: 100px;
                 
            }
            .ul{
                margin: auto;
                display: inline-block;
                position: relative; /*相对定位*/
                z-index: 2;
                left: 830px;
                top: 0px;
                 
            }
             
#buttons span {
    cursor: pointer;
    font-size: 15px;
    text-align: center;
    font-family: "微软雅黑";
    float: left;
    border: 1px solid #fff;
    width: 20px;
    height: 20px;
    border-radius: 50%;  /*设置为圆形*/
    /*background: #333; */
    margin-right: 15px; /*设置圆形的间隔为15像素*/
}
#buttons .on { 
    background: orangered;   /*选中的按钮样式*/
}
 
        </style>