body {
    font-family: Arial, sans-serif;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-color: #f4f4f4;
    color: #333;
    text-align: center;
    padding: 20px;
}
.container {
    background-color: #fff;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 600px;
    margin-bottom: 20px;
}
h1, h2 {
    color: #555;
    margin-bottom: 20px;
}
.invitation-image {
    max-width: 100%;
    height: auto;
    margin-bottom: 30px;
    border-radius: 4px;
}
.button-group {
    display: flex;
    flex-direction: column;
    gap: 15px;
    margin-top: 20px;
}
.button-group a {
    padding: 12px 25px;
    background-color: #007bff;
    color: white;
    text-decoration: none;
    border-radius: 4px;
    font-size: 1.1em;
    transition: background-color 0.3s ease;
}
.button-group a:hover {
    background-color: #0056b3;
}
.flashes {
    list-style: none;
    padding: 0;
    margin: 20px 0;
}
.flashes .success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
    padding: 10px;
    border-radius: 4px;
}
.flashes .danger {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
    padding: 10px;
    border-radius: 4px;
}
.flashes .info {
    background-color: #d1ecf1;
    color: #0c5460;
    border: 1px solid #bee5eb;
    padding: 10px;
    border-radius: 4px;
}
form div {
    margin-bottom: 15px;
}
form label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}
form input[type="text"],
form input[type="email"],
form input[type="password"] {
    width: calc(100% - 22px);
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
}
form button {
    padding: 10px 20px;
    background-color: #28a745;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1.1em;
    margin-top: 10px;
}
form button:hover {
    background-color: #218838;
}
.back-link {
    display: block;
    margin-top: 20px;
    text-align: center;
    color: #007bff;
    text-decoration: none;
}
.back-link:hover {
    text-decoration: underline;
}
.qr-code-img {
    max-width: 250px;
    height: auto;
    margin: 20px auto;
    border: 1px solid #ddd;
    border-radius: 4px;
}