<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<script type="text/javascript">
function changes(x){ //声明一个函数
x.style.background="red"; //改变边框的背景色
x.style.borderRadius="50px"; //改变边框的弧度
}
</script>
</head>
<body>
<div style="width: 200px;height: 200px;background-color: #ccc;border:1px solid #000;margin: 0 auto;" onclick="changes(this)">
</div>
</body>
</html>