代码示例:(标识:css3_border-radius_3)
<!DOCTYPE html>
<html>
<head>
<style> 
#rcorners1 {
  border-radius: 50px / 15px;
  background: #73AD21;
  padding: 20px; 
  width: 200px;
  height: 150px; 
}

#rcorners2 {
  border-radius: 15px / 50px;
  background: #73AD21;
  padding: 20px; 
  width: 200px;
  height: 150px; 
}

#rcorners3 {
  border-radius: 50%;
  background: #73AD21;
  padding: 20px; 
  width: 200px;
  height: 150px;
} 
</style>
</head>
<body>

<h1>border-radius 属性</h1>

<p>椭圆边框 - border-radius: 50px / 15px:</p>
<p id="rcorners1"></p>

<p>椭圆边框 - border-radius: 15px / 50px:</p>
<p id="rcorners2"></p>

<p>椭圆边框 - border-radius: 50%:</p>
<p id="rcorners3"></p>

</body>
</html>
运行结果: