String cvcNumber = request.getCvc();
bool isCardAccepted = inRange("500", "539", cvcNumber);
bool isCardRejected = inRange("540", "549", cvcNumber);

if(isCardAccepted){
    templateResponse = GetTransformedTemplateResponse("Authentication Accepted!", "acceptMessage", request.getAcceptURL());
}
else if(isCardRejected) {
    templateResponse = GetTransformedTemplateResponse("...", "...", ...);
}
else {
    templateResponse = GetTransformedTemplateResponse("...", "...", ...);
}

epdqCardAuthResponse.setHtmlAnswer(encodeToBase64(templateResponse));


private void templateResponse GetTransformedTemplateResponse(string outcome, string color, string url) {
    templateResponse = templateResponse.replace("$REPLACE_OUTCOME$",outcome);
    templateResponse = templateResponse.replace("$REPLACE_OUTCOME_COLOR$",color);
    templateResponse = templateResponse.replace("$REPLACE_URL$", url);
    return template
}