uber.css

.iframe-container {
  -webkit-margin-start: -20px;
  -webkit-transition: margin 100ms, opacity 100ms;
  bottom: 0;
  left: 0;
  opacity: 0;
  position: absolute;
  right: 0;
  top: 0;
  z-index: 1;
}

.iframe-container.selected {
  -webkit-margin-start: 0;
  -webkit-transition: margin 200ms, opacity 200ms;
  -webkit-transition-delay: 100ms;
  opacity: 1;
  z-index: 2;
}