code: function handleDocumentMousemove(e) {
    let annotationId = overlay.getAttribute('data-target-id');
    let parentNode = overlay.parentNode;
    let rect = parentNode.getBoundingClientRect();
    let y = (dragStartY + (e.clientY - dragOffsetY));
    let x = (dragStartX + (e.clientX - dragOffsetX));
    let minY = 0;
    let maxY = rect.height;
    let minX = 0;
    let maxX = rect.width;
  
    if (y > minY && y + overlay.offsetHeight < maxY) {
      overlay.style.top = `${y}px`;
    }
  
    if (x > minX && x + overlay.offsetWidth < maxX) {
      overlay.style.left = `${x}px`;
    }
  }
docs: Handle document.mousemove event
  
  @param {Event} e The DOM event that needs to be handled