llRect(0,0,W,H);
            ctx.fillStyle = '#fff'; ctx.font = '900 46px ui-sans-serif, system-ui';
            ctx.fillText('Paused', 24, 64);
          }
        }

        function startCountdown(done) {
          const seq = ['3','2','1','Go!'];
          let i = 0;
          countdownEl.style.display = 'grid';
          countdownEl.textContent = seq[i];
          const id = setInterval(() => {
            i++;
            if (i >= seq.length) { clearInterval(id); countdownEl.style.display = 'none'; do