const keys = Array.from(document.querySelectorAll(".key"));
const keysList = keys.map(keyEl => keyEl.dataset.key).map(str => Number(str));
console.log(keys);
document.addEventListener("keyup", event => {
if (keysList.includes(event.keyCode)) {
console.log("play sound");
const audio = document.querySelector(`audio[data-key="${event.keyCode}"]`);
const key = document.querySelector(`.key[data-key="${event.keyCode}"]`);
key.classList.add("playing");
audio.play();
}
});
keys.forEach(key =>
key.addEventListener("transitionend", e => {
e.target.classList.remove("playing");
})
);