问角度计数中的计时器不正确

EN

startRound() {
    const startTime = new Date();
    this.roundIntervalId = setInterval(() => {
      this.timeLeft--;
      if ((new Date() - startTime) / 1000) > 30 {
        clearInterval(this.roundIntervalId);
      }
    }, 1000);
  }

// Please choose a static date and make it the same on every tab
var endTime = new Date(new Date().getTime() + 60000);

function loop() {
  var timeLeft = Math.floor((endTime.getTime() - new Date().getTime()) / 1000);
  console.log('Time left: ' + timeLeft);
  if (timeLeft <= 0) {
    console.log('Time up!');
    return;
  }
  setTimeout(() => loop(), 1000 - new Date().getMilliseconds());
}

function startRound() {
  // Wait till next second before starting
  setTimeout(() => loop(), 1000 - new Date().getMilliseconds());
}