/* 全ページ共通：ページ上部へ戻る船型ボタン */
.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 26px;
  z-index: 1000;
  display: inline-grid;
  width: 62px;
  height: 62px;
  grid-template-rows: 27px 13px;
  gap: 1px;
  place-items: center;
  padding: 0;
  color: #ffffff;
  cursor: pointer;
  visibility: hidden;
  background: #075f9b;
  border: 1px solid rgba(255, 255, 255, 0.75);
  border-radius: 50%;
  box-shadow: 0 8px 22px rgba(7, 55, 91, 0.28);
  opacity: 0;
  transform: translateY(12px);
  transition:
    opacity 0.22s ease,
    transform 0.22s ease,
    background-color 0.22s ease,
    visibility 0.22s ease;
}

.back-to-top.is-visible {
  visibility: visible;
  opacity: 1;
  transform: translateY(0);
}

.back-to-top:hover,
.back-to-top:focus-visible {
  background: #1596d2;
  transform: translateY(-3px);
}

.back-to-top:focus-visible {
  outline: 3px solid rgba(21, 150, 210, 0.35);
  outline-offset: 3px;
}

.back-to-top svg {
  width: 27px;
  height: 27px;
  overflow: visible;
}

.back-to-top-label {
  font-size: 9px;
  font-weight: 700;
  line-height: 1;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

@media (max-width: 820px) {
  .back-to-top {
    right: 16px;
    bottom: 18px;
    width: 56px;
    height: 56px;
    grid-template-rows: 24px 12px;
  }

  .back-to-top svg {
    width: 24px;
    height: 24px;
  }

  .back-to-top-label {
    font-size: 8px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .back-to-top {
    transition: none;
  }
}