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Insecure Resource

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CSS

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CSS Base

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                  <ul class="acdmenu">
    <li aria-expanded="true"><a href="#">アコーディオン1</a>
      <ul>
        <li><a href="#">アコーディオン1の子1</a></li>
        <li><a href="#">アコーディオン1の子2</a></li>
        <li><a href="#">アコーディオン1の子3</a></li>
      </ul>
    </li>
    <li aria-expanded="false"><a href="#">アコーディオン2</a>
      <ul>
        <li><a href="#">アコーディオン2の子1</a></li>
        <li><a href="#">アコーディオン2の子2</a></li>
        <li><a href="#">アコーディオン2の子3</a></li>
      </ul>
    </li>
    <li aria-expanded="false"><a href="#">アコーディオン3</a>
      <ul>
        <li><a href="#">アコーディオン3の子1</a></li>
        <li><a href="#">アコーディオン3の子2</a></li>
        <li><a href="#">アコーディオン3の子3</a></li>
      </ul>
    </li>
  </ul>
!

CSS 

              
                .acdmenu ul {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease-out;
}

.acdmenu li[aria-expanded="true"] > ul {
  max-height: 1000px;
  transition: max-height 0.3s ease-out;
}


/* 装飾用 */
.acdmenu{
  margin:0;
  padding:0;
  background:#BE92A2;
  list-style:none;
  ul{
    margin:0;
    padding:0;
    list-style:none;
  }
    >li{
    >a{
      padding:10px 16px;
      &::before{
        content:"add";
        font-family: 'Material Icons';
        display:inline-block;
        transition: transform .2s ease-in-out;
      }
      &:hover{
        background:#DBBADD;
      }
    }
    li{
      >a{
        padding:8px 16px 8px 32px;
        &:hover{
          background:#96CDFF;
        }
      }
    }
  }
  li{
    a{
      display:block;
      color:#333;
      text-decoration:none;
      transition:all .2 ease-in-out;
    }
    ul{
      background:#D8E1FF;
      li{
        // padding-left:1em;
      }
    }
    &[aria-expanded="true"]{
      >a{
        &::before{
          transform: rotate(-405deg);
        }
      }
    }
  }
}
!

JS 

              
                // クリックイベントをリッスンしてアコーディオンをトグルする
const accordionItems = document.querySelectorAll('.acdmenu > li');
const firstAccordionItem = accordionItems[0];

// 最初の li 要素を開く
firstAccordionItem.setAttribute('aria-expanded', true);
const firstUl = firstAccordionItem.querySelector('ul');
if (firstUl) {
  firstUl.style.display = 'block';
}

accordionItems.forEach(item => {
  item.addEventListener('click', event => {
    const currentItem = event.currentTarget;
    const isItemExpanded = currentItem.getAttribute('aria-expanded') === 'true';

    // すべてのアイテムを閉じる
    accordionItems.forEach(item => {
      item.setAttribute('aria-expanded', false);
      const ul = item.querySelector('ul');
      if (ul) {
        ul.style.display = 'none';
      }
    });

    // クリックされたアイテムを開く
    if (!isItemExpanded) {
      currentItem.setAttribute('aria-expanded', true);
      const ul = currentItem.querySelector('ul');
      if (ul) {
        ul.style.display = 'block';
      }
    }
  });
});
!
999px

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