source: Dev/trunk/src/client/dojox/form/resources/TriStateCheckBox.css

/* TriStateCheckBox
 * 
 * Styling TriStateCheckBox mainly includes:
 * 
 * 1. Containers
 *              .dojoxTriStateCheckBox|.dojoxTriStateCheckBoxIcon - for border, padding, width|height and background image
 * 
 * 2. Checked state
 *              .dojoxTriStateCheckBoxChecked - for checked background-color|image
 *              .dojoxTriStateCheckBoxMixed - for mixed background-color|image
 * 
 * 3. Hover state
 *              .dojoxTriStateCheckBoxHover|.dojoxTriStateCheckBoxCheckedHover|.dojoxTriStateCheckBoxMixedHover - for background image
 * 
 * 4. Disabled state
 *              .dojoxTriStateCheckBoxDisabled|.dojoxTriStateCheckBoxCheckedDisabled|.dojoxTriStateCheckBoxMixedDisabled - for background image
 */
.claro .dojoxTriStateCheckBox, .claro .dojoxTriStateCheckBoxIcon {
  background-image: url('images/tristatecheckboxStates.png');
  /* checkbox sprite image */

  background-repeat: no-repeat;
  width: 15px;
  height: 16px;
  margin: 0 2px 0 0;
  padding: 0;
}
.dj_ie6 .claro .dojoxTriStateCheckBox, .dj_ie6 .claro .dojoxTriStateCheckBoxIcon {
  background-image: url('images/tristatecheckboxStates.png');
  /* checkbox sprite image */

}
.claro .dojoxTriStateCheckBox{
  /* unchecked */

  background-position: -15px;
}
.claro .dojoxTriStateCheckBoxChecked{
  /* checked */

  background-position: 0px;
}
.claro .dojoxTriStateCheckBoxMixed {
  /* mixed */

  background-position: -30px;
}
.claro .dojoxTriStateCheckBoxDisabled {
  /* disabled and unchecked */

  background-position: -105px;
}
.claro .dojoxTriStateCheckBoxCheckedDisabled {
  /* disabled and checked */

  background-position: -90px;
}
.claro .dojoxTriStateCheckBoxMixedDisabled {
  /* disabled and mixed */

  background-position: -120px;
}
.claro .dojoxTriStateCheckBoxHover {
  /* hovering over and unchecked */

  background-position: -60px;
}
.claro .dojoxTriStateCheckBoxCheckedHover {
  /* hovering over and checked */

  background-position: -45px;
}
.claro .dojoxTriStateCheckBoxMixedHover {
  /* hovering over and mixed */

  background-position: -75px;
}

.dijit_a11y .dojoxTriStateCheckBoxHover .dojoxTriStateCheckBoxInner,
.dijit_a11y .dojoxTriStateCheckBoxFocused .dojoxTriStateCheckBoxInner{
        /* focused or hovering over */
        border: dashed;
}

.dijit_a11y .dojoxTriStateCheckBoxHover .dojoxTriStateCheckBoxInner,
.dijit_a11y .dojoxTriStateCheckBoxFocused .dojoxTriStateCheckBoxInner{
        /* focused or hovering over */
        border: solid;
}

.dijit_a11y .dojoxTriStateCheckBoxDisabled .dojoxTriStateCheckBoxInner{
        /* focused or hovering over */
        opacity: 0.5;
}

.dj_ie .dijit_a11y .dojoxTriStateCheckBoxDisabled .dojoxTriStateCheckBoxInner{
        /* disabled */
}


.dojoxTriStateCheckBoxInner{
  /* inner text */

  visibility: hidden;
  display: none;
        position: absolute;
        text-align: center;
}

.dijit_a11y .dojoxTriStateCheckBoxInner{
  /* inner text */
  
  visibility: visible;
        display: block;
}

.dojoxTriStateCheckBoxInput {
        /* place the actual input on top, but all-but-invisible */
        opacity: 0.01;
        padding: 0;
        margin: 0,
        border: 0;
        width: 15px;
        height: 16px;
        background-position:center center;
        background-repeat:no-repeat;
}

.dj_ie .dojoxTriStateCheckBoxInput {
        filter: alpha(opacity=0);
}