~~~
<style>
.box{
width:100px;
height: 100px;
background: pink;
position: relative;
}
.box::after{
position: absolute;
content: "";
border:7px solid transparent;
border-left-color: pink;
right: -14px;
top:10px;
}
</style>
~~~
~~~
<body>
<div class="box"></div>
</body>
~~~
效果图如下：
