.form-control.is-invalid,
.form-select.is-invalid {
    border-color: #dc3545;
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12' width='12' height='12' fill='none' stroke='%23dc3545'%3e%3ccircle cx='6' cy='6' r='4.5'/%3e%3cpath fill='%23dc3545' d='M6 3v3m0 3v.001'/%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right calc(0.375em + 0.1875rem) center;
    background-size: calc(0.75em + 0.375rem) calc(0.75em + 0.375rem);
    padding-right: calc(1.5em + 0.75rem);
}

.form-control.is-invalid:focus,
.form-select.is-invalid:focus {
    border-color: #dc3545;
    box-shadow: 0 0 0 0.2rem rgba(220, 53, 69, 0.25);
}

.invalid-feedback {
    display: block;
    color: #dc3545;
    font-size: 0.875em;
    margin-top: 0.25rem;
}