Javascript server time

  /*
  <table>
    <td id="relogio" data-server-time="<?php echo date('Y,m,d,H,i,s'); ?>"></td>
  </table>
  */

  let agoraValue = 0;

  const doDom = () => {
    const relogio = document.querySelector("#relogio");
    const b = relogio.getAttribute("data-server-time").split(",");
    const agora = new Date(b[0], (b[1]-1), b[2], b[3], b[4], b[5]);
    agoraValue = agora.valueOf();
    setInterval(iniciaCronometro,1000);
  };

  const iniciaCronometro = () => {
    const myDate = new Date(agoraValue);
    const h = myDate.getHours();
    const i = ("0" + String(myDate.getMinutes())).slice(-2);
    relogio.innerHTML = h+':'+i;
    agoraValue = agoraValue + 1000;
  };

  // Await DOM to be loaded
  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', () => {
      doDom();
    });
  } else {
    doDom();
  }