回答編集履歴

  document.addEventListener('click',e=>{

  const t=e.target;

  const tbody=targetTable.querySelector('tbody');

  const tr=`<tr><td>${namae.value}</td><td>${nickname.value}</td><td><input type="button" value="del" class="del"></td></tr>`;

  tbody.insertAdjacentHTML('beforeend',tr);

  }

  t.closest('tr').remove();

  }

  tuikaBtn.toggleAttribute('hidden',tbody.querySelectorAll('tr').length>=3);