举例子

        div{
            width: 1000px;
            height: 700px;
            border: 1px solid red;
            /*默认全部平铺*/
            background-image: url("images/img.jpg");
        }

        /*水平平铺*/
        .div1{
            background-repeat: repeat-x;
        }

        /*竖直平铺*/
        .div2{
            background-repeat: repeat-y;
        }

        /*不平铺*/
        .div3{
            background-repeat: no-repeat;
        }

.title{
    font-size: 18px;
    font-weight: bold;
    text-indent: 1em;
    line-height: 30px;
    /*颜色 图片 图像位置 平铺方式*/
    background: #f6f6f6 url("../images/down.png") 260px 1px no-repeat;
}
/*ul li*/

/*
list-style:
  none; 去掉圆点
  circle：空心圆
  decimol：数字
  squre：正方形
*/

#nav{
    width:300px;
    background: pink;
}

ul{
    background: pink;
}

ul li{
    height: 30px;
    list-style: none;
    text-indent: 1em;
    background: pink url("../images/right.png") 230px 1px no-repeat;
}



a{
    text-decoration: none;
    color: black;
}

a:hover{
    text-decoration: underline;
    color: red;

}