.ig-invitation-form {
    max-width: 400px;
    border: 1px solid #ccc;
    padding: 20px;
    margin: 20px 0;
    font-family: Arial, sans-serif;
    background: #fefefe;
}
.ig-invitation-form input,
.ig-invitation-form textarea {
    width: 100%;
    padding: 10px;
    margin-bottom: 15px;
    border: 1px solid #ddd;
}
.ig-invitation-form button {
    background: #0073aa;
    color: #fff;
    padding: 10px 15px;
    border: none;
    cursor: pointer;
}
.ig-invitation-form button:hover {
    background: #005177;
}
.ig-message-box {
    margin-bottom: 10px;
    font-weight: bold;
}