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/*css style */
#up {
width:0px;
height:0px;
border-bottom:10px solid #89b007;
border-left:10px solid #fff;
border-right:10px solid #fff;
}
#down {
width:0px;
height:0px;
border-top:10px solid #89b007;
border-left:10px solid #fff;
border-right:10px solid #fff;
}
#left {
width:0px;
height:0px;
line-height:0px; /*解决ie出现梯形问题*/
border-right:10px solid #89b007;
border-top:10px solid #fff;
border-bottom:10px solid #fff;
}
#right {
width:0px;
height:0px;
line-height:0px; /*解决ie出现梯形问题*/
border-left:10px solid #89b007;
border-top:10px solid #fff;
border-bottom:10px solid #fff;
}
#trapezoid {
width:7px;
height:15px;
border-bottom:10px solid #89b007;
border-left:10px solid #fff;
border-right:10px solid #fff;
}