@namespace url(http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul);

*:not(#TabsToolbar):not(.tab-content) > .close-icon{
  list-style-image: url("chrome://classic_theme_restorer/content/images/close_w10i.png") !important;
  -moz-image-region: rect(0, 20px, 20px, 0) !important;
}
*:not(#TabsToolbar):not(.tab-content) > .close-icon:hover{
  -moz-image-region: rect(0, 40px, 20px, 20px) !important;
}
*:not(#TabsToolbar):not(.tab-content) > .close-icon:hover:active {
  -moz-image-region: rect(0, 60px, 20px, 40px) !important;
}
*:not(#TabsToolbar):not(.tab-content) > .close-icon > .toolbarbutton-icon {
  width: 16px !important;
}