Is it possible to add a colored badge background to a user title?

Product Support
10 
span.moderator i:after {
  content: "TEXT";
  display: inline-block;
  background-color: #00cccc;
  border-radius: 10%;
  font-size: 1em;
  font-weight: bold;
  padding: 0.4em;
  color: #fff;
}
span.moderator i:before {
  display: none;
}

Adding

SITE/admin/customize/themes