界面：
代碼：
<!DOCTYPE html>
<html>
<head>
<title>註冊</title>
<style type="text/css">
.login-form{
width: 400px;
height: 300px;
margin:100px auto;
border:1px solid #00aaff;
position: relative;
}
.form-content{
/*position: absolute;*/
text-align: center;
}
input{
width:170px;
margin-left: 20px;
margin-top: 20px;
height: 25px;
border: 1px solid #00aaff;
}
input[type="submit"]{
background-color: #00aaff;
color: white;
width: 220px;
height: 27px;
border-radius: 10px;
}
</style>
</head>
<body>
<form class="login-form">
<div class="form-content">
<h2>註冊</h2>
<div>
<span>賬號:</span><input type="text" name="用戶名" pattern="[A-z]{5,}" required title="只能是5位以上的英文字符">
</div>
<div>
<span>密碼:</span><input type="password" name="密碼">
</div>
<div>
<span style="margin-left: -29px">確認密碼:</span><input type="password" name="密碼">
</div>
<input type="submit" name="註冊">
</div>
</form>
</body>
</html>