CSS - -moz-image-region

Example

#example-button {
  /* display only the 4x4 area from the top left of this image */
  list-style-image: url("chrome://example/skin/example.png");
  -moz-image-region: rect(0px, 4px, 4px, 0px);
}
#example-button:hover {
  /* use the 4x4 area to the right of the first for the hovered button */
  -moz-image-region: rect(0px, 8px, 4px, 4px);
}

Syntax  

<a href="css/-moz-image-region#shape"><shape></a><p>where <br><code><shape> = rect(<top>, <right>, <bottom>, <left>)</code></p>

Description  

For certain XUL elements and pseudo-elements that use an image from the list-style-image property, this property specifies a region of the image that is used in place of the whole image. This allows elements to use different pieces of the same image to improve performance.

The syntax is similar to the clip property. All four values are relative to the upper left corner of the image.

License