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    background-position: center;
    opacity: 0.08;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    -webkit-filter: grayscale(40%);
    -moz-filter: grayscale(40%);
    -ms-filter: grayscale(40%);
    -o-filter: grayscale(40%);
    filter: grayscale(40%);
    filter: gray;
}
.cnblogs-markdown pre {
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}
.cnblogs-markdown pre > span {
  position: absolute;
  top: 0;
  right: 0;
  border-radius: 3px;
  padding:0 10px;
  font-size: 12px;
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  color: #000;
  cursor: pointer;
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  margin:8px 10px;
  transition: background .5s;
  -moz-transition: background .5s;
  -webkit-transition: background .5s;
  -o-transition: background .5s;
}
.cnblogs-markdown pre > span:hover {
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}
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}