Как добавить плюс 1, если ответ правильный в API перетаскивания на JavaScript?

window.addEventListener("DOMContentLoaded", () => { // when page has loaded
  const target = document.getElementById("drop_area");
  const source = document.getElementById("drag_options");
  const resetBut = document.getElementById("reset");
  const runBut = document.getElementById("run");
  const answerDiv = document.getElementById("answers");
  let dragged = null;

  source.addEventListener("dragstart", (event) => {
    // store a ref. on the dragged elem
    dragged = event.target;
  });

  target.addEventListener("dragover", (event) => {
    // prevent default to allow drop
    event.preventDefault();
  });

  target.addEventListener("drop", (event) => {
    // prevent default action (open as link for some elements)
    event.preventDefault();
    // move dragged element to the selected drop target
    if (event.target.dataset.value) {
      // dragged.parentNode.removeChild(dragged);
      event.target.textContent = dragged.textContent;
    }
  });

  const pointsPerCorrect = 5;
  runBut.addEventListener("click", () => {
    const correct = [...target.querySelectorAll("div")].filter(div => div.textContent === div.dataset.value); // run filter on the child divs
    const numberOfCorrect = correct.length;
    const answers = correct.map(div => div.textContent).join(", ");
    answerDiv.innerHTML = `You had ${numberOfCorrect} answer${numberOfCorrect===1?"":"s"} correct.<br/> ${answers}`; // using template strings
  });
  resetBut.addEventListener("click", () => {
    target.querySelectorAll("div").forEach((div,i) => div.textContent = (i+1));
  });
});

#drop_area {
  background-color: green;
}

#drag_options {
  background-color: red;
}

#drop_area div {
  padding: 2px;
  border: 1px solid black;
}

#drag_options div {
  padding: 2px;
  border: 1px solid black;
}

<div id = "drop_area">
  <div data-value = "10000 Years">1</div>
  <div data-value = "Evil Queen">2</div>
  <div data-value = "12">3</div>
  <div data-value = "Nana">4</div>
  <div data-value = "Maurice">5</div>
</div>
<hr/>
<div id = "drag_options">
  <div draggable = "true">Evil Queen</div>
  <div draggable = "true">Maurice</div>
  <div draggable = "true">Nyla</div>
  <div draggable = "true">Cruella de Vil</div>
  <div draggable = "true">4</div>
  <div draggable = "true">Moris</div>
  <div draggable = "true">10000 Years</div>
  <div draggable = "true">1000 Years</div>
  <div draggable = "true">12</div>
  <div draggable = "true">Nana</div>
</div>

<div id = "submit_button">
  <button type = "button" id = "reset">Reset</button>
  <button type = "button" id = "run">Submit</button>
</div>
<div id = "handler">
  <div id = "score_board">
    <div id = "wrap">
      <h1>SCORE</h1>
      <div id = "answers"></div>
    </div>
  </div>
</div>