.image-lightbox__trigger {
  cursor: zoom-in;
}

.image-lightbox {
  width: min(1200px, calc(100% - 2rem));
  max-width: none;
  max-height: calc(100dvh - 2rem);
  margin: auto;
  /* 閉じるボタン用の領域を確保し、画像と重ならないようにする。 */
  padding: 4.5rem 0 0;
  border: 0;
  background: transparent;
  overflow: visible;
  opacity: 0;
  filter: blur(0.75rem);
  transform: translateY(1rem) scale(0.93);
  transition:
    opacity 0.5s ease,
    filter 0.6s ease,
    transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

.image-lightbox.is-open {
  opacity: 1;
  filter: blur(0);
  transform: translateY(0) scale(1);
}

.image-lightbox::backdrop {
  background: rgb(3 7 12 / 88%);
  backdrop-filter: blur(0);
  opacity: 0;
  transition: opacity 0.5s ease, backdrop-filter 0.7s ease;
}

.image-lightbox.is-open::backdrop {
  backdrop-filter: blur(0.5rem);
  opacity: 1;
}

.image-lightbox__image {
  display: block;
  max-width: 100%;
  max-height: calc(100dvh - 6.5rem);
  margin: auto;
  object-fit: contain;
  opacity: 0;
  filter: blur(0.5rem);
  transform: scale(1.045);
  transition:
    opacity 0.55s ease 0.12s,
    filter 0.75s ease 0.12s,
    transform 0.85s cubic-bezier(0.16, 1, 0.3, 1) 0.12s;
}

.image-lightbox__viewport {
  max-width: 100%;
}

.image-lightbox__swipe-hint {
  display: none;
}

/* スワイプ対象はあえて画面幅より広く表示し、フリック操作を促す。 */
.image-lightbox.is-pannable {
  width: 100vw !important;
  max-width: 100vw !important;
}

.image-lightbox.is-pannable .image-lightbox__viewport {
  width: 100vw;
  max-width: 100vw;
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scrollbar-width: none;
  touch-action: pan-x;
}

.image-lightbox.is-pannable .image-lightbox__viewport::-webkit-scrollbar {
  display: none;
}

.image-lightbox.is-pannable .image-lightbox__image {
  width: auto !important;
  max-width: none !important;
  height: 80dvh !important;
  max-height: 80dvh;
}

.image-lightbox.is-pannable .image-lightbox__swipe-hint {
  display: block;
  margin: 0.9rem 0 0;
  color: rgb(255 255 255 / 82%);
  font-size: 1.3rem;
  letter-spacing: 0.08em;
  text-align: center;
}

.image-lightbox.is-pannable .image-lightbox__close {
  right: 1rem;
}

.image-lightbox__image.is-changing {
  opacity: 0;
  filter: blur(0.35rem);
  transform: scale(0.985);
  transition-duration: 0.16s;
}

.image-lightbox.is-open .image-lightbox__image {
  opacity: 1;
  filter: blur(0);
  transform: scale(1);
}

@media (min-width: 768px) {
  .image-lightbox {
    width: calc(100vw - 4rem);
    max-width: none;
  }

  .image-lightbox__image {
    width: 100%;
    max-height: calc(100dvh - 7rem);
  }
}

.image-lightbox__close {
  position: absolute;
  z-index: 1;
  top: 0;
  right: 0;
  display: grid;
  width: 3rem;
  height: 3rem;
  place-items: center;
  padding: 0;
  border: 1px solid rgb(255 255 255 / 55%);
  border-radius: 50%;
  background-color: rgb(18 18 18 / 68%);
  background-image:
    linear-gradient(45deg, transparent 47%, #fff 48%, #fff 52%, transparent 53%),
    linear-gradient(-45deg, transparent 47%, #fff 48%, #fff 52%, transparent 53%);
  background-repeat: no-repeat;
  background-position: center;
  background-size: 1.15rem 1.15rem;
  box-shadow: 0 0.25rem 1rem rgb(0 0 0 / 25%);
  color: transparent;
  cursor: pointer;
  font-size: 0;
  line-height: 0;
  opacity: 0;
  transform: translateY(-0.5rem);
  transition:
    background-color 0.25s ease,
    opacity 0.35s ease 0.3s,
    transform 0.45s cubic-bezier(0.16, 1, 0.3, 1) 0.3s;
}

.image-lightbox.is-open .image-lightbox__close {
  opacity: 1;
  transform: translateY(0);
}

.image-lightbox.is-open .image-lightbox__close:hover {
  background-color: rgb(18 18 18 / 90%);
  transform: rotate(90deg) scale(1.06);
}

.image-lightbox__close:focus-visible,
.image-lightbox__trigger:focus-visible {
  outline: 3px solid #1a9ee5;
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  .image-lightbox,
  .image-lightbox::backdrop,
  .image-lightbox__image,
  .image-lightbox__close {
    transition-duration: 0.01ms;
  }
}