getClientXY = (event) => {
  let clientX = 0,
    clientY = 0
  if (event.type.startsWith('mouse')) {
    clientX = /** @type {MouseEvent} */ (event).clientX
    clientY = /** @type {MouseEvent} */ (event).clientY
  } else if (event.type.startsWith('touch')) {
    clientX = /** @type {TouchEvent} */ (event).touches[0].clientX
    clientY = /** @type {TouchEvent} */ (event).touches[0].clientY
  }
  return { clientX, clientY }
}
@param {MouseEvent | TouchEvent} event
@returns {{ clientX: number, clientY: number }}