Background video mute toggle

<script>
document.addEventListener('DOMContentLoaded', function() {
var toggleSoundButton = document.querySelector('.fa-volume-mute');
var heroBackgroundVideo = document.querySelector('.herovideo video');
toggleSoundButton.addEventListener('click', function (event) {

if (heroBackgroundVideo.muted !== false){
heroBackgroundVideo.muted=false;
toggleSoundButton.classList.add('fa-volume-up');
} else {
heroBackgroundVideo.muted=true;
toggleSoundButton.classList.remove('fa-volume-up');
} }); });
</script>