二、代码
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>登录</title><style>body {background-color: #f1f1f1;}.login-box {width: 400px;margin: 50px auto;padding: 20px;background-color: #fff;border-radius: 5px;box-shadow: 0 0 10px rgba(0, 0, 0, 0.3);}.form-group {margin-bottom: 20px;}label {display: block;margin-bottom: 5px;font-weight: bold;}input[type="text"], input[type="password"] {width: 100%;padding: 10px;border: none;border-bottom: 1px solid #ccc;outline: none;font-size: 14px;}button[type="submit"] {display: block;width: 100%;padding: 10px;background-color: #4CAF50;color: #fff;border: none;border-radius: 5px;cursor: pointer;}button[type="submit"]:hover {background-color: #3e8e41;}</style>
</head>
<body><div class="login-box"><h2>登录</h2><form><div class="form-group"><label for="username">用户名：</label><input type="text" id="username" name="username"></div><div class="form-group"><label for="password">密码：</label><input type="password" id="password" name="password"></div><button type="submit">登录</button></form></div>
</body>
</html>
