.form-check-input[type=radio]:checked {
    background-image: url("data:image/svg+xml,%3Csvg width='12' height='9' viewBox='0 0 12 9' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1.3335 3.99999L4.66683 7.33333L10.6668 1.33333' stroke='white' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E%0A");
    background-size: 50%;
}