function cleanup() {
    var images = document.getElementsByTagName('img');
    for (var i = 0; i < images.length; i++) {
        if (images[i].src === 'https://www.classmarker.com/img/[email protected]') {
            images[i].style.opacity = '0';
        } else if (images[i].src === 'https://www.classmarker.com/img/[email protected]') {
            images[i].src = 'https://www.classmarker.com/img/[email protected]';
        }
    }

    var chosen = document.getElementsByClassName('chosen');
    for (var i = 0; i < chosen.length; i++) {
        chosen[i].style.display = 'none';
    }

    var headlinetop = document.getElementsByClassName('headlinetop');
    for (var i = 0; i < headlinetop.length; i++) {
        headlinetop[i].style.display = 'none';
    }

    var quiz = document.getElementsByClassName('dotted_quiz');
    for (var i = 0; i < quiz.length; i++) {
        quiz[i].style.display = 'none';
    }

    var testres = document.getElementsByClassName('testres')[0];
    testres.style.display = 'none';

    var answer = document.getElementById('answerKeyContainer');
    answer.style.display = 'none';
}

cleanup();