.series-title {
  background: #333;
  padding: 1.6rem 0;
}
.series-title h2 {
  font-size: 16px;
  font-size: 1.6rem;
  line-height: 1.6rem;
  color: #FFF;
  text-align: center;
  vertical-align: top;
}
.series-title h2 span {
  font-size: 12px;
  font-size: 1.2rem;
  margin-right: 10px;
  vertical-align: top;
  border-bottom: 2px solid rgba(255,255,255,.3);
}
.series-title h2 a {
  color: #FFF;
}

/* article-series-link
=========================================================== */
#article-series-link {
  display: flex;
  flex-grow: 1;
  justify-content:space-between;
  padding-block: 1px 10px;
  margin: 0 -5px;

  /* 通常と異なる余白 */
  &.diff-space {
    padding-block: 20px 10px;
  }

  > li {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    text-align: center;
    flex-grow: 1;
    font-size: 16px;
    font-size: 1.6rem;
    font-weight: 700;
    margin: 0 5px;
    padding: 0;
    line-height: 1.15;

    &::before {
      display: none;
    }

    /* 下線 */
    &::after {
      content: "";
      display: block;
      height: 3px;
      border-radius: 2px;
      background-color: #949494;
    }
  }

  > li.is-current {
    flex-grow: 2;
    color: #e90708;

    /* 下線 */
    &::after {
      background-color: #f83e3f;
    }
  }

  > li > a {
    padding-bottom: 7px;
    color: #595959;
  }
}

/* article-series-next-link
=========================================================== */
/* TODO: 詳細度で勝てないため、 id で設定している、将来的には class にしたい */
#article-series-next-link {
  display: block;
  padding: 16px;
  margin: 0 auto 24px;
  border: 2px solid #bbb;
  color: #767676;
  position: relative;
  max-width: 375px;
  border-radius: 4px;
}

.article-series-next-link__label {
  font-size: 1.6rem;
  line-height: 1.4;
  color: #767676;
}

.article-series-next-link__text {
  color: #2379ca;
  text-decoration: underline;
}

/* series-modal
=========================================================== */
body.is-fixed {
  overflow: hidden;
}

.series-nav {
  display: flex;
  align-items: center;
  gap: 10px;
}

.series-nav__open-btn {
  width: fit-content;
  appearance: none;
  border: none;
  background: none;
  padding: 0;
  margin: 0;
  font-size: 1.4rem;
  font-weight: bold;
  color: inherit;
  flex: 0 0 auto;
  white-space: nowrap;
  display: none;

  &:is(:hover, :focus-visible) {
    opacity: 0.7;
  }
}

.testb .series-nav__open-btn {
  display: block;
}

.series-nav__btn-icon {
  display: grid;
  gap: 5px;
  place-items: center;
  margin-bottom: 3px;
  pointer-events: none;
}

.series-nav__btn-icon-row {
  position: relative;
  display: block;
  width: 20px;
  height: 3px;
  margin-left: 6px;
  background: #333;
  border-radius: 20px;
}

.series-nav__btn-icon-row::before {
  content: "";
  position: absolute;
  top: 50%;
  left: -6px;
  width: 4px;
  height: 4px;
  background: #333;
  border-radius: 50%;
  transform: translateY(-50%);
}

.series-nav__btn-label {
  pointer-events: none;
}

.series-modal {
  position: fixed;
  inset: 0;
  z-index: 1003;
  width: 100%;
  height: 100%;
  max-width: none;
  max-height: none;
  padding: 0;
  border: 0;
  margin: 0;
  background: transparent;
  color: inherit;
}

.series-modal::backdrop {
  background: rgba(0, 0, 0, 0.5);
}

.series-modal__inner {
  position: absolute;
  inset: 120px 0;
  margin: auto;
  max-width: calc(100% - 50px);
  height: auto;
}

.series-modal__close-btn {
  position: absolute;
  top: -10px;
  right: -10px;
  width: 40px;
  height: 40px;
  appearance: none;
  padding: 0;
  border: 1px solid #000;
  border-radius: 50%;
  background: #000;
  z-index: 2;
}

.series-modal__close-btn::before,
.series-modal__close-btn::after {
  position: absolute;
  right: 0;
  left: 0;
  display: inline-block;
  content: "";
  box-sizing: border-box;
  width: calc(100% - 10px);
  height: 2px;
  margin: 0 auto;
  border-radius: 4px;
  background: #fff;
}

.series-modal__close-btn::before {
  top: 18px;
  transform: rotate(-315deg);
}

.series-modal__close-btn::after {
  bottom: 18px;
  transform: rotate(315deg);
}

.series-modal__content {
  height: auto;
  width: 100%;
  max-height: 100%;
  background-color: #fff;
  padding: 20px 20px 50px;
  overflow-y: auto;
  border-radius: 10px;
}

.series-modal__content ol {
  list-style: none;
  margin: 0;

  li {
    margin: 0;
    padding: 0;
  }

  li+li {
    margin-top: 20px;
  }
}

.series-modal .series-modal__content .series-modal__title {
  width: fit-content;
  margin: 10px auto 20px;
  font-size: 1.5rem;
}

.series-modal .series-modal__content .series-modal__title::before {
  display: none;
}

.series-modal .series-modal__content .series-modal__content-item {
  position: relative;
  display: block;
  line-height: 1.6;
  color: #333;
  word-break: inherit;

  .series-modal__content-text {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    border-bottom: 1px dashed rgb(0 0 0 / 0.3);
    padding-bottom: 20px;
    margin-left: 30px;
  }

  &::before {
    position: absolute;
    z-index: 1;
    top: 0;
    left: 0;
    display: block;
    box-sizing: border-box;
    width: 17px;
    height: 17px;
    content: "";
    border: 3px solid #000;
    border-radius: 100%;
    background: #fff;
    transition: all 0.3s ease-out;
  }
}

.series-modal .series-modal__content .series-modal__content-item:is(:hover, :focus-visible) {
  padding-bottom: 0;
  color: inherit;
  word-break: inherit;

  .series-modal__content-text {
    opacity: 0.7;
  }

  &::before {
  background: #000;
  }
}

.series-modal .series-modal__content li:not(:last-child) .series-modal__content-item::after {
  position: absolute;
  z-index: 1;
  top: 17px;
  bottom: -20px;
  left: 8px;
  display: block;
  width: 1px;
  content: "";
  background: #000;
}

.series-modal .series-modal__content .series-modal__content-item.is-current {
  font-weight: bold;
  pointer-events: none;

  &::before {
    background-color: #000;
  }
}

.series-modal__more-btn {
  width: fit-content;
  appearance: none;
  display: block;
  border: solid 1px #000;
  background: none;
  padding: 10px 20px;
  margin: 30px auto 0;
  color: inherit;
  font-weight: bold;

  &[hidden] {
    display: none;
  }

  &:is(:hover, :focus-visible) {
    opacity: 0.7;
  }
}