body {
    background-color: #f8f9fa;
}

.card {
    border-radius: 10px;
    border: none;
}

.invalid-feedback {
    display: none;
    width: 100%;
    margin-top: 0.25rem;
    font-size: 0.875em;
    color: #dc3545;
}

.was-validated .form-control:invalid ~ .invalid-feedback,
.was-validated .form-control:invalid ~ .invalid-feedback {
    display: block;
}