.denba-question-navi {
  --dn-navy: #17345c;
  --dn-blue: #245a98;
  --dn-soft: #f4f7fb;
  --dn-line: #d9e2ee;
  --dn-text: #233247;
  margin: 72px 0;
  padding: 0 24px;
  color: var(--dn-text);
  font-family: "Noto Sans JP", "Hiragino Kaku Gothic ProN", sans-serif;
}

.denba-question-navi__inner {
  max-width: 920px;
  margin: 0 auto;
  padding: 48px;
  border: 1px solid var(--dn-line);
  border-radius: 20px;
  background: #fff;
  box-shadow: 0 18px 48px rgba(23, 52, 92, 0.08);
}

.denba-question-navi__eyebrow {
  margin: 0 0 10px;
  color: var(--dn-blue);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.16em;
}

.denba-question-navi h2 {
  margin: 0;
  color: var(--dn-navy);
  font-size: clamp(24px, 3vw, 34px);
  line-height: 1.45;
}

.denba-question-navi__lead {
  margin: 14px 0 28px;
  color: #5b6879;
  font-size: 15px;
  line-height: 1.9;
}

.denba-question-navi__list {
  border-top: 1px solid var(--dn-line);
}

.denba-question-navi__item {
  border-bottom: 1px solid var(--dn-line);
}

.denba-question-navi__item summary {
  position: relative;
  display: flex;
  align-items: center;
  gap: 16px;
  min-height: 68px;
  padding: 14px 46px 14px 4px;
  color: var(--dn-navy);
  font-size: 16px;
  font-weight: 700;
  line-height: 1.65;
  cursor: pointer;
  list-style: none;
}

.denba-question-navi__item summary::-webkit-details-marker {
  display: none;
}

.denba-question-navi__item summary::after {
  content: "+";
  position: absolute;
  right: 8px;
  top: 50%;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--dn-soft);
  color: var(--dn-blue);
  font-size: 22px;
  font-weight: 400;
  line-height: 28px;
  text-align: center;
  transform: translateY(-50%);
}

.denba-question-navi__item[open] summary::after {
  content: "−";
}

.denba-question-navi__number {
  flex: 0 0 auto;
  color: #7d8ca0;
  font-size: 12px;
  letter-spacing: 0.08em;
}

.denba-question-navi__answer {
  padding: 0 48px 24px 36px;
}

.denba-question-navi__answer p {
  margin: 0;
  color: #4c5c70;
  font-size: 15px;
  line-height: 1.95;
}

.denba-question-navi__answer a,
.denba-question-navi__all a {
  display: inline-block;
  margin-top: 14px;
  color: var(--dn-blue);
  font-size: 14px;
  font-weight: 700;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.denba-question-navi__item.is-handoff .denba-question-navi__answer {
  margin-bottom: 18px;
  padding: 20px 24px;
  border-radius: 12px;
  background: var(--dn-soft);
}

.denba-question-navi__all {
  margin: 28px 0 0;
  text-align: right;
}

@media (max-width: 640px) {
  .denba-question-navi {
    margin: 48px 0;
    padding: 0 16px;
  }

  .denba-question-navi__inner {
    padding: 30px 20px;
    border-radius: 16px;
  }

  .denba-question-navi__lead {
    margin-bottom: 20px;
    font-size: 14px;
  }

  .denba-question-navi__item summary {
    gap: 10px;
    min-height: 64px;
    padding-right: 40px;
    font-size: 15px;
  }

  .denba-question-navi__answer {
    padding: 0 40px 22px 28px;
  }

  .denba-question-navi__answer p {
    font-size: 14px;
  }

  .denba-question-navi__item.is-handoff .denba-question-navi__answer {
    padding: 18px;
  }

  .denba-question-navi__all {
    text-align: left;
  }
}

@media (prefers-reduced-motion: reduce) {
  .denba-question-navi * {
    scroll-behavior: auto !important;
  }
}