css之多行文本输出

<div class="desc" title="Jennifer Joanna Aniston (born February 11, 1969)[1] is an American actress, producer, and businesswoman.[2] The daughter of Greek actor John Aniston and American actress Nancy Dow, Aniston gained worldwide recognition for portraying Rachel Green on the popular television sitcom Friends (1994–2004), a role which earned her a Primetime Emmy Award, a Golden Globe Award, and a Screen Actors Guild Award. The character was widely popular during the airing of the series and was later recognized as one of the 100 greatest female characters in United States television">
 Jennifer Joanna Aniston (born February 11, 1969)[1] is an American actress, producer, and businesswoman.[2] The daughter of Greek actor John Aniston and American actress Nancy Dow, Aniston gained worldwide recognition for portraying Rachel Green on the popular television sitcom Friends (1994–2004), a role which earned her a Primetime Emmy Award, a Golden Globe Award, and a Screen Actors Guild Award. The character was widely popular during the airing of the series and was later recognized as one of the 100 greatest female characters in United States television
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</div>

.desc {
 position: relative;
 width: 400px;
 /*用像素表示，不要用em，以免造成不同浏览器下计算出现小数点取舍不同导致1像素的差距【行高*截取行数】*/
 overflow: hidden;
 max-height: 72px;
 font-size: 16px;
 line-height: 24px;
 overflow: hidden;
 word-wrap: break-word;
 /*强制打散字符*/
 word-break: break-all;
 background: #fff;
 /*同背景色*/
 color: #fff;

 &:after,
 &:before {
 content: attr(title);
 position: absolute;
 left: 0;
 top: 0;
 width: 100%;
 /*实际文本颜色*/
 color: #000;
 }
 &:before {
 display: block;
 overflow: hidden;
 /*显示在最上面，展示前面的(截取行数-1)行字符*/
 z-index: 1;
 /*根据行高和截取行数调整，值为[(截取行数-1)*行高]*/
 max-height: 48px;
 /*同背景色*/
 background: #fff;
 }
 &:after {
 display: -webkit-box;
 -webkit-box-orient: vertical;
 -webkit-box-sizing: border-box;
 box-sizing: border-box;
 /*截取行数*/
 -webkit-line-clamp: 3;
 /*行首缩进字符数，值为[(截取行数-1)*尾部留空字符数]*/
 text-indent: -8em;
 /*尾部留空字符数*/
 padding-right: 4em;
 }
 button {
 width: 40px;
 height: 20px;
 font-size: 12px;
 padding: 0;
 outline: 0;
 position: absolute;
 right: 0;
 bottom: 0;
 }
}