1 .userCard .sanjiao {//三角形的制作； 2     width: 0; 3     height: 0; 4     border-left: 10px solid transparent; 5     border-right: 10px solid transparent; 6     border-bottom: 10px solid rgba(0, 0, 0, .9); 7     margin: -23px 0 0 -10px; 8     left: 50%; 9     position: absolute10 }