Mozilla Firefox Specific Styles selector

moz-styles.css

/*
* Common styles across all browsers
*/

.selector {
  /*
  * Normal styles
  */
}

/*
* Write/Load the -moz overrides at the end/last
* to override.
*/

@-moz-document url-prefix() { 
  .selector {
     /*
     * Override specific styles
     * Eg: margin,padding, position:absolute etc
     */
  }
}