body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #ffffff;
    height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
}

header {
    background-color: rgba(28, 108, 178, 0.9);
    color: white;
    padding: 20px 0;
    text-align: center;
    width: 100%;
}

main {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    position: relative;
}

.content {
    background-color: rgba(255, 255, 255, 0.8);
    padding: 20px;
    border-radius: 10px;
    text-align: center;
    position: absolute;
}

h2 {
    color: #1c6cb2;
}

.login-form {
    margin-bottom: 20px;
}

.login-form input {
    display: block;
    margin: 10px auto;
    padding: 10px;
    font-size: 16px;
    width: 80%;
    max-width: 300px;
    margin-bottom: 20px;  /* 增加外边距 */
}

.buttons {
    display: flex;
    justify-content: center;
    gap: 10px;
}

.login-form button,
.btn {
    padding: 10px 20px;
    background-color: #1c6cb2;
    color: white;
    border: none;
    border-radius: 5px;
    text-decoration: none;
    display: inline-block;
    line-height: 20px;
    cursor: pointer;
}

.login-form button:hover,
.btn:hover {
    background-color: #155a8c;
}

footer {
    background-color: rgba(28, 108, 178, 0.9);
    color: white;
    text-align: center;
    padding: 10px 0;
    width: 100%;
}

.error-message {
    color: red;
    font-size: 12px;
    text-align: left;
    margin-top: -10px;
    margin-bottom: 10px;
}