code-block-buttons.css

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

pre .btnIcon {
  position: absolute;
  top: -5px;
  right: 16px;
  z-index: 2;
  cursor: pointer;
  border: 1px solid transparent;
  padding: 0;
  background-color: transparent;
  height: 30px;
  transition: all 0.25s ease-out;
  display: none;
}

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

pre code[class*="language-"]:hover + .btnIcon {
  display: block;
}

.btnIcon__body {
  align-items: center;
  display: flex;
  color: #535b64;
}

.btnIcon svg {
  fill: currentColor;
  margin-right: 0.4em;
}

.btnIcon__label {
  font-size: 11px;
}