('keydown', (e) => {
        if (e.key === 'Enter') { e.preventDefault(); submitAnswer(); }
        else if (e.key === 'Escape') { e.preventDefault(); els.answer.value = ''; }
        else if (e.key === 'Tab') { e.preventDefault(); skip(); }
      });
      for (const el of [els.difficulty, els.duration, ...Object.values(els.ops)]) {
        el.addEventListener('change', () => { summarizeMode(); updateHighUI(); });
      }
      summarizeMode();
      updateHighUI();
    })();
  </script>
</body>
</html>
