website/static/css/code-blocks-buttons.css

/* "Copy" code block button */
pre {
  position: relative;
}

pre .btnIcon {
  position: absolute;
  top: 4px;
  z-index: 2;
  cursor: pointer;
  border: 1px solid transparent;
  padding: 0;
  color: #fff;
  background-color: transparent;
  height: 30px;
  transition: all .25s ease-out;
}

pre .btnIcon:hover {
  text-decoration: none;
}

.btnIcon__body {
  align-items: center;
  display: flex;
}

.btnIcon svg {
  fill: currentColor;
  margin-right: .4em;
}

.btnIcon__label {
  font-size: 11px;
}

.btnClipboard {
  right: 10px;
}