.root {
  position: relative;
}

.scroller {
  overflow-y: auto;
}

.scroller_max-height {
  max-height: 400px;
}

.root .button {
  position: absolute;
  top: 15px;
  right: 15px;
  opacity: 0;
  transition: opacity 0.2s ease;
}

.root:hover .button {
  opacity: 1;
}

.root pre {
  border-radius: 2px;
  padding: 12px 20px;
}