.centered {
  text-align: center;
}

.right-aligned {
  float: right;
  display: inline-block;
}

img {
  max-height: inherit;
  max-width: inherit;
}

.size-small {
  max-height: 10em;
  max-width: 10em;
}

.size-large {
  max-height: 20em;
  max-width: 20em;
}

ol.sources {
  list-style: none;
  counter-reset: num;
}

ol.sources > li {
  counter-increment: num;
}

ol.sources > li::before {
  content: "[" counter(num) "]";
}