CSS hack

/*  by  司徒正美 2011.6.1*/

      #element {
        background:orange;/* FF4 safari5 */
      }
      #element {
        *background: blue;    /* IE7*/
      }
      #element {
        -background: red;     /* IE6 */
      }


      #element {
        background: green\0; /* IE8  opera11 */
      }

      :root #element { background:pink\9; }  /* IE9 */

      @media screen and (-ms-high-contrast: active), (-ms-high-contrast: none) {  /*IE10*/
        #element { background:lightgreen;
      }

//所有版本的 Firefox
@-moz-document url-prefix() {
  .selector {
     color:lime;
  }
}