三角形向左向右
.left{
? ? ?display: inline-block;
? width: 0;
? height: 0;
? margin-left: 2px;
? vertical-align: middle;
? border-right:4px solid;
? border-top: 4px solid transparent;
? border-bottom: 4px solid transparent;
}
.right{
? ? ?display: inline-block;
? width: 0;
? height: 0;
? margin-left: 2px;
? vertical-align: middle;
? border-left:4px solid;
? border-top: 4px solid transparent;
? border-bottom: 4px solid transparent;
}
2015-12-24
或者：
left== border:?4px solid?transparent; border-right:4px solid;
right== ?border:?4px solid?transparent; border-left:4px solid;
2015-12-24
http://dev.yesky.com/89/33282589.shtml