<!doctype html>
<html>
<head>
<meta charset="UTF-8">
<title>css对话气泡</title>
<style>
.test-div{
position: relative;
width:150px;
height: 36px;
border:black 1px solid;
border-radius:5px;
background: rgba(245,245,245,1) ;
}
.test-div:before,.test-div:after{
content: "";
display: block;
position: absolute;
top:8px;
width: 0;
height: 0;
border:6px transparent solid;
}
.test-div:before{
left:-11px;
border-right-color: rgba(245,245,245,1);
z-index:1;
}
.test-div:after{
left:-12px;
border-right-color: rgba(0,0,0,1);
z-index: 0 ;
}
/*前后各画一个三角形，通过改变位置和堆叠顺序，使两个三角形部分覆盖重合*/
</style>
</head>
<body>
<div class="test-div"></div>
</body>
</html>