/* Move down content because we have a fixed navbar that is 50px tall 
body {
  padding-top: 50px;
  padding-bottom: 20px;
}
*/

.img-responsive {
  display: block;
  width: auto;
  max-height: 50%;
}

.img-small {
  max-height: 20px;
}

iframe {
  margin-left: auto;   /* Automatic margin from left */
  margin-right: auto; /* Automatic margin from right */
 }