/* 代码复制按钮 */
.cnblogs-markdown pre {
  position: relative;
}
.cnblogs-markdown pre > .copy-btn {
  position: absolute;
  top: 8px;
  right: 8px;
  background: rgba(0,0,0,0.5);
  color: #fff;
  padding: 4px 8px;
  border-radius: 4px;
  font-size: 12px;
  cursor: pointer;
  display: none;
}
.cnblogs-markdown pre:hover > .copy-btn {
  display: block;
}