<!doctype html>
<title>CSS Test Reference</title>
<link rel="author" title="Emilio Cobos Álvarez" href="mailto:emilio@crisal.io">
<link rel="author" title="Mozilla" href="https://mozilla.org">
<style>
  #test {
    background-color: green;
    width: 200px;
    height: 200px;
  }
</style>
<p>Test passes if there is a green 200px times 200px square.</p>
<div id="test"></div>