/*标签名查找*/            span            {                color: orange;            }            /*id查找*/            #aa            {                width: 100px;                height: 100px;                background-color: red;            }            /*class查找*/            .bb            {                width: 100px;                height: 100px;                background-color: red;            }            /*并列*/            .cc,#dd            {                width: 100px;                height: 100px;                background-color: red;            }            /*父代*/            #wai #li            {                width: 100px;                height: 100px;                background-color: red;            }            /*父代,并列*/            #wai #li,.limian            {                width: 100px;                height: 100px;                background-color: red;            }