如何在 javascript 测验中更改正确答案的颜色

Question

I am making a javascript quiz: multiple choice with four options. When the answer is correct, I want it turn green before moving onto the next question, if incorrect I want it to turn red and the correct answer to flash green

Edits I have tried make the colour carry over into the next question. Any suggestions?

var currentQuestion =0;
var score = 0;
var totQuestions = questions.length;

var container = document.getElementById('quizContainer');
var questionEl = document.getElementById('question');
var opt1 = document.getElementById('opt1');
var opt2 = document.getElementById('opt2');
var opt3 = document.getElementById('opt3');
var opt4 = document.getElementById('opt4');
var nextButton = document.getElementById('nextButton');
var resultCont = document.getElementById('result');

function loadQuestion(questionIndex) {
var q = questions[questionIndex];
questionEl.textContent = (questionIndex +1)+ '.' + q.question;
opt1.textContent = q.option1;
opt2.textContent = q.option2;
opt3.textContent = q.option3;
opt4.textContent = q.option4;};


document.getElementById('opt1').onclick = function   loadNextQuestion    (){
var selectedOption = document.getElementById('opt1');

var answer = 1;
if(questions[currentQuestion].answer == answer){
score +=1;
}
selectedOption.clicked = false;
currentQuestion++;
if(currentQuestion == totQuestions - 1) {
nextButton.textContent = 'Finish';
 }
if (currentQuestion == totQuestions) {
container.style.display ='none';
resultCont.style.display = '';
resultCont.textContent = 'You scored ' + score;
return;
}
loadQuestion(currentQuestion);
}

Repeated three times four opt2, opt3 and opt 4

Answer 1

This is solved via CSS. You can apply classes to your selected elements as the state requires. I'm not sure which element in your code represents a "correct" answer, but you would get a reference to that and add or remove a class as necessary. Ex:

document.querySelector('.myCorrectAnswerElement').classList.add('greenSuccessClass');

Answer 2

Hope this sample will help you.

HTML:

<div id="item" > I am just a div</div>
    <button id="yes">yes</button>
    <button id="no">no</button>

CSS:

    #item{
    width: 500px;
    height: 30px;
    background-color: red;
}

JS:

var item = document.getElementById("item");
var yes = document.getElementById("yes");
var no = document.getElementById("no");

yes.onclick = function(){
    item.style.backgroundColor = "red";
}

no.onclick = function(){
    item.style.backgroundColor = "green";
}