<!DOCTYPE html>
<html lang="zh">
<head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no"><title>登录界面</title><style>* {margin: 0;padding: 0;box-sizing: border-box;}body {font-family: Arial, sans-serif;background-color: #f4f4f4;min-height: 90vh;max-height: 100vh;}.login-container {display: flex;justify-content: center;align-items: flex-start; width: 100%;height: 100%;}.login-box {background-color: white;padding: 30px;box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);border-radius: 8px;width: 100%;max-width: 400px;box-sizing: border-box;margin-top: 100px;}h2 {text-align: center;margin-bottom: 20px;}.input-group {margin-bottom: 20px;}.input-group label {display: block;font-size: 14px;color: #333;margin-bottom: 8px;}.input-group input {width: 100%;padding: 10px;font-size: 14px;border: 1px solid #ddd;border-radius: 4px;outline: none;}.input-group input:focus {border-color: #007bff;}.input-group button {width: 100%;padding: 10px;font-size: 16px;background-color: #007bff;color: white;border: none;border-radius: 4px;cursor: pointer;transition: background-color 0.3s;}.input-group button:hover {background-color: #0056b3;}@media (max-width: 390px) {.login-box {padding: 20px;max-width: 90%;}h2 {font-size: 24px;}.input-group input,.input-group button {font-size: 16px;padding: 12px;}}</style>
</head>
<body><div class="login-container"><div class="login-box"><h2>登录</h2><form action="#"><div class="input-group"><label for="username">用户名</label><input type="text" id="username" placeholder="请输入用户名" required></div><div class="input-group"><label for="password">密码</label><input type="password" id="password" placeholder="请输入密码" required></div><div class="input-group"><button type="submit">登录</button></div></form></div></div>
</body>
</html>