before和after的两个四色块不应该是一个在前面一个在后面吗，效果怎么不是呢？还有一个问题是before和after设置的border应该是正方型的 这个怎么显示是长方形
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
*{
margin: 0;
padding: 0;
}
.one{
/* height: 200px; */
/* width: 200px; */
width: 0px;
height: 0px;
/* background-color: aquamarine; */
margin-top: 100px;
border: 50px solid red;
/* border-top-width: 0px ; */
/* border-color: red blue green yellow; */
/* border-color: transparent transparent green transparent; */
}
.one::before{
content: "";
border: 50px solid red;
border-color: red blue green yellow;
}
.one::after{
content: "";
border: 50px solid red;
/* margin-top: 100px; */
/* margin-left: 100px; */
width: 0px;
height: 0px;
/* border-color: blue transparent transparent transparent; */
border-color: red blue green yellow;
}
.two{
height: 100px;
width: 100px;
background-color: brown;
}
</style>
</head>
<body>
<div class="one"></div>
<!-- <div class="two"></div> -->
</body>
</html>
```和发生背景
