document.addEventListener('DOMContentLoaded', _ => {
  const info = document.getElementById('info');
  const updateInfo = event => {
    const { clientX, clientY, pageX, pageY } = event;
    info.innerHTML = `clientX: ${clientX} clientY: ${clientY}<br />  pageX: ${pageX} pageY: ${pageY}`;
  };
  document.addEventListener('mouseover', updateInfo);
  document.addEventListener('mousemove', updateInfo);
});