css文字溢出实现,考虑兼容性

单行：

overflow: hidden;
text-overflow:ellipsis;
white-space: nowrap;

多行：

display: -webkit-box;
-webkit-box-orient: vertical;
-webkit-line-clamp: 3; //行数
overflow: hidden;

兼容：

p{position: relative; line-height: 20px; max-height: 40px;overflow: hidden;}
p::after{content: "..."; position: absolute; bottom: 0; right: 0; padding-left: 40px;
background: -webkit-linear-gradient(left, transparent, #fff 55%);
background: -o-linear-gradient(right, transparent, #fff 55%);
background: -moz-linear-gradient(right, transparent, #fff 55%);
background: linear-gradient(to right, transparent, #fff 55%);
}