.faq {
    background-color: #E9F7FB;
}
.faq_conatiner {
    margin-top: 40px;
    border-top: 1px solid #D9D9D9;
}
.faq_item {
    border-bottom: 1px solid #D9D9D9;
}

.faq_item .faq_item_title {
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
    padding: 25px 40px 25px 25px;
    cursor: pointer;
}


.faq_item .faq_item_title::after {
    position: absolute;
    content: '';
    right: 20px;
    transform: translateY(-25%) rotate(45deg);
    width: 10px;
    height: 10px;
    margin-left: 10px;
    border-bottom: 3px solid #231815;
    border-right: 3px solid #231815;
    transition: transform .3s;
}

.faq_item[open] .faq_item_title::after {
    transform: rotate(225deg);
}

.faq_item .faq_item_text {
    position: relative;
    transform: translateY(-8px);
    opacity: 0;
    margin: 0;
    max-height: 0;
    overflow: hidden;
    padding: 0px 40px;
    transition:
    max-height .9s ease,
    transform .9s ease,
    padding .9s ease;
}

.faq_item.opening .faq_item_text,
.faq_item.closing .faq_item_text {
  will-change: max-height, opacity, transform;
}
.faq_item[open] .faq_item_text {
    padding: 16px 40px;
    transform: none;
    transform: translateY(0);
    max-height: 600px;
    opacity: 1;
}
@media only screen and (max-width: 680px) {
    .faq_item .faq_item_text {
        padding-top: 0;
    }
    .faq_item .faq_item_title {
        padding: 25px 40px 25px 16px;
    }
}
details {
  /* --------アコーディオンの中身のスタイル-------- */
  &::details-content {
    transition: height 0.4s, content-visibility 0.4s allow-discrete;
    height: 0;
    opacity: 0;
    overflow: clip;
  }

  /* --------アコーディオンの中身のスタイル（開いている時）-------- */
  &[open]::details-content {
    opacity: 1;
  }

  /* アコーディオンが開いた時のスタイル */
  &[open] .icon {
    transform: rotate(180deg);
  }
}

@supports (interpolate-size: allow-keywords) {
  :root {
    interpolate-size: allow-keywords; /* height:0（数値型） → auto（文字型） のアニメーションを可能にするための指定 */
  }
  details[open]::details-content {
    height: auto;
  }
}

@supports not (interpolate-size: allow-keywords) {
  details[open]::details-content {
    height: 150px;
    overflow-y: scroll; /* 溢れる場合はスクロール可能にする */
  }
}