index.js

for (var i = 0; i < document.querySelectorAll(".drum").length; i++) {

  document.querySelectorAll(".drum")[i].addEventListener("click", function() {

    var buttonpress = this.innerHTML;

    makesound(buttonpress);
    buttonanimation(buttonpress);

  });
}

document.addEventListener("keypress", function() {
  makesound(event.key);
  buttonanimation(event.key);
});

function makesound(x) {

  switch (x) {
    case "w":
      var crash = new Audio("sounds/crash.mp3");
      crash.play();
      break;

    case "a":
      var crash = new Audio("sounds/kick-bass.mp3");
      crash.play();
      break;

    case "s":
      var crash = new Audio("sounds/snare.mp3");
      crash.play();
      break;

    case "d":
      var crash = new Audio("sounds/tom-1.mp3");
      crash.play();
      break;

    case "j":
      var crash = new Audio("sounds/tom-2.mp3");
      crash.play();
      break;

    case "k":
      var crash = new Audio("sounds/tom-3.mp3");
      crash.play();
      break;

    case "l":
      var crash = new Audio("sounds/tom-4.mp3");
      crash.play();
      break;

    default:
      console.log(button.innerHTML);
  }
}


function buttonanimation(y){
  var activeButton = document.querySelector("." + y);
  activeButton.classList.add("pressed");
  setTimeout(function(){
    activeButton.classList.remove("pressed");
  },.100);
}