/*添加按钮*/
.cnblogs-markdown pre {
  position: relative;
}
.cnblogs-markdown pre > span {
  position: absolute;
  top: 0;
  right: 0;
  border-radius: 2px;
  padding: 0 10px;
  font-size: 12px;
  background: rgba(0, 0, 0, 0.4);
  color: #fff;
  cursor: pointer;
  display:none;
}
.cnblogs-markdown pre:hover > span {
  display:block;
}
.cnblogs-markdown pre > .copyed {
  background: #67c23a;
}