text: function answer_click(answer_container) {
      let checkbox = answer_container.getElementsByTagName('input')[0];
      if (!answer_container.classList.contains('selected')) {
          answer_container.classList.add('selected');
          checkbox.checked = true;
      } else {
          answer_container.classList.remove('selected');
          checkbox.checked = false;
      }
  }
  
  
  function solution_check(e, form) {
      let inputs = form.getElementsByTagName("input");
      for (let i = 0; i < inputs.length; ++i) {
          if (inputs[i].getAttribute("type") === "checkbox" && inputs[i].checked) {
              return;
          }
      }
      e.preventDefault();
      let answers_container = form.children[2];
      if (!answers_container.classList.contains("error_answers")) {
          answers_container.classList.add("error_answers");
          let paragraph = document.createElement("p");
          paragraph.innerText = "Оберіть варіант відповіді";
          paragraph.className = "error";
          answers_container.insertBefore(paragraph, answers_container.firstChild);
      }
  }
  