sample.user.css

/* ==UserStyle==
@name         Sample
@version      0.0.3
@description  Just a sample to test my self hosted Stylus stuff
@namespace    tst2005/self-hosted-sample
@author       tst2005
@homepageURL  https://github.com/usercss/sample
@supportURL   https://github.com/usercss/sample/issues
@updateURL    https://github.com/usercss/sample/raw/master/sample.user.css
@license      MIT
@preprocessor uso
==/UserStyle== */
@-moz-document domain("example.net"), domain("foo.example.net") {
  .non-existant.sample {
     display: none;
  }
}