媒体查询

  header{
            background:orange;
        }
        h1{
            color:red;
        }
        h2{
            color:blue;
        }



        @media all and (min-width:1024px){
            h2{
                display:none;
            }
        }
        @media all and (max-width:1023px){
            h1{
                display:none;
            }

        }