以下代码实现的图形对应正确是?
:before {
content:'';
width:0;
height:0;
border-left:10px solid red;
border-top:10px solid red;
border-bottom:10px solid transparent;
}
content:'';
width:0;
height:0;
border-left:10px solid red;
border-top:10px solid red;
border-bottom:10px solid transparent;
}