如何使可拖动元素在同一位置重现

#draggable {
  position: absolute;
  width: 100px;
  height: 100px;
  background-color: #ccc;
  cursor: move;
}

var draggable = document.getElementById('draggable');
var offsetX, offsetY;

draggable.addEventListener('mousedown', function(e) {
  offsetX = e.clientX - draggable.offsetLeft;
  offsetY = e.clientY - draggable.offsetTop;
  
  document.addEventListener('mousemove', dragElement);
  document.addEventListener('mouseup', stopDragging);
});

function dragElement(e) {
  draggable.style.left = (e.clientX - offsetX) + 'px';
  draggable.style.top = (e.clientY - offsetY) + 'px';
}

function stopDragging() {
  document.removeEventListener('mousemove', dragElement);
  document.removeEventListener('mouseup', stopDragging);
}