framework/ember/app/styles/flarum/badges.less

.badges {
  margin: 0;
  padding: 0;
  list-style: none;

  &, & > li {
    display: inline-block;
  }
}

.badge-size(@size) {
  width: @size;
  height: @size;
  border-radius: @size / 2;
  line-height: @size - 4px;
  &, & .fa {
    font-size: 0.6 * @size;
  }
}
.badge {
  .badge-size(24px);
  border: 2px solid @fl-body-bg;
  background: @fl-body-muted-color;
  color: #fff;
  display: inline-block;
  vertical-align: middle;
  text-align: center;

  & .label {
    display: none;
  }
}