text: window.addEventListener('keydown', function(e){
  
      const audio = this.document.querySelector(`audio[data-key="${e.keyCode}"]`);
      // const key = this.document.querySelector(`.key[data-key="${e.keyCode}"]`);
      const border = this.document.querySelector(`.border[data-key="${e.keyCode}"]`);
  
      // this.console.log(border);
      if(!audio) return;  
      audio.currentTime = 0;
      audio.play();
      border.classList.add('playing');
  });
  
  
  function removeTransition(e){
      if(e.propertyName !== 'transform')return;
      // console.log(e.propertyName);
      this.classList.remove('playing');
      
  }
  
  const keys = document.querySelectorAll('.border');
  keys.forEach(border => border.addEventListener('transitionend', removeTransition));
  // console.log(keys);