/* 开屏风景向下滚动时折叠成第一枚邮票 */
.intro-overlay {
  animation: none;
  background: var(--hero-bg);
  cursor: default;
}
.intro-overlay::after {
  z-index: 8;
  opacity: 0.26;
}
.intro-art-frame {
  position: absolute;
  z-index: 1;
  left: 50%;
  top: 50%;
  width: 100vw;
  height: 100vh;
  transform: translate(-50%, -50%);
  border: 0 solid var(--cream);
  filter: drop-shadow(0 0 0 transparent);
}
.intro-art-frame > .intro-opening-art,
.intro-art-frame > .intro-final-art {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.intro-opening-art {
  display: block;
}
.intro-final-art {
  opacity: 0;
}
.intro-teeth {
  position: absolute;
  z-index: 4;
  pointer-events: none;
  opacity: 0;
  background: radial-gradient(circle, var(--cream) 7px, transparent 7.5px) center/18px 18px;
}
.intro-teeth.top,
.intro-teeth.bottom {
  height: 18px;
  left: -2px;
  right: -2px;
}
.intro-teeth.top {
  top: -9px;
}
.intro-teeth.bottom {
  bottom: -9px;
}
.intro-teeth.left,
.intro-teeth.right {
  width: 18px;
  top: -2px;
  bottom: -2px;
}
.intro-teeth.left {
  left: -9px;
}
.intro-teeth.right {
  right: -9px;
}
.intro-stamp-inscription,
.intro-stamp-title {
  position: absolute;
  z-index: 5;
  color: var(--cream);
  opacity: 0;
  text-shadow: 0 2px 4px #172a2480;
}
.intro-stamp-inscription {
  top: 14px;
  left: 14px;
  right: 14px;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  font:
    900 22px/1 Cenzo,
    Impact,
    sans-serif;
}
.intro-stamp-inscription b {
  border: 1.5px solid currentColor;
  padding: 2px 5px;
}
.intro-stamp-title {
  left: 14px;
  right: 14px;
  bottom: 14px;
  font-size: clamp(22px, 2.4vw, 33px);
  line-height: 1.05;
}
.intro-copy {
  inset: 15% auto auto 10%;
  width: min(68vw, 950px);
  align-items: flex-start;
  justify-content: flex-start;
  text-align: left;
  transform: none;
  animation: none;
  z-index: 4;
}
.intro-meta {
  width: min(580px, 65vw);
  font-size: 12px;
}
.intro-copy strong {
  font-size: clamp(70px, 11vw, 150px);
  line-height: 0.95;
  margin: 38px 0 26px;
  color: #f4e9cf;
}
.intro-copy small {
  font-size: 13px;
  letter-spacing: 0.18em;
  padding: 0;
  color: #f4e9cf;
}
.intro-scroll {
  position: absolute;
  z-index: 9;
  right: 6%;
  bottom: 8%;
  display: flex;
  align-items: center;
  gap: 20px;
  border: 1.5px solid #f4e9cf;
  border-radius: 40px;
  background: #1f574d;
  color: #f4e9cf;
  padding: 12px 18px;
  font-size: 12px;
  letter-spacing: 0.1em;
}
.intro-scroll span {
  font-size: 22px;
  line-height: 1;
}
.intro-scroll:hover {
  background: #f4e9cf;
  color: #1f574d;
}
.intro-overlay.leaving {
  pointer-events: none;
  animation: intro-overlay-release 1.65s ease-in-out forwards;
}
.leaving .intro-art-frame {
  animation: intro-fold-scene 1.65s cubic-bezier(0.22, 0.78, 0.24, 1) forwards;
}
.leaving .intro-copy {
  animation: intro-title-release 0.65s ease-in forwards;
}
.leaving .intro-scroll {
  animation: intro-title-release 0.35s ease-in forwards;
}
.leaving .intro-opening-art {
  animation: intro-landscape-out 1.65s linear forwards;
}
.leaving .intro-final-art {
  animation: intro-stamp-art-in 1.65s linear forwards;
}
.leaving .intro-teeth,
.leaving .intro-stamp-inscription,
.leaving .intro-stamp-title {
  animation: intro-details-in 1.65s linear forwards;
}
@keyframes intro-fold-scene {
  0% {
    width: 100vw;
    height: 100vh;
    border-width: 0;
    filter: drop-shadow(0 0 0 transparent);
  }
  25% {
    width: 100vw;
    height: 100vh;
    border-width: 0;
  }
  80%,
  100% {
    width: var(--intro-target-w);
    height: var(--intro-target-h);
    border-width: 14px;
    filter: drop-shadow(18px 17px 6px #161e1840);
  }
}
@keyframes intro-landscape-out {
  0%,
  64% {
    opacity: 1;
  }
  82%,
  100% {
    opacity: 0;
  }
}
@keyframes intro-stamp-art-in {
  0%,
  65% {
    opacity: 0;
  }
  84%,
  100% {
    opacity: 1;
  }
}
@keyframes intro-details-in {
  0%,
  64% {
    opacity: 0;
  }
  82%,
  100% {
    opacity: 1;
  }
}
@keyframes intro-title-release {
  to {
    opacity: 0;
    transform: translateY(-45px);
  }
}
@keyframes intro-overlay-release {
  0%,
  90% {
    opacity: 1;
  }
  100% {
    opacity: 0;
  }
}
@media (max-width: 650px) {
  .intro-copy {
    inset: 18% 7% auto;
    width: 86%;
    align-items: center;
    text-align: center;
  }
  .intro-meta {
    width: 100%;
    font-size: 10px;
  }
  .intro-copy strong {
    font-size: clamp(55px, 14vw, 88px);
    margin: 30px 0 18px;
  }
  .intro-copy small {
    font-size: 10px;
  }
  .intro-scroll {
    left: 50%;
    right: auto;
    bottom: 8%;
    transform: translateX(-50%);
    white-space: nowrap;
    font-size: 10px;
    padding: 10px 14px;
  }
  .intro-stamp-inscription {
    font-size: 18px;
    top: 9px;
    left: 9px;
    right: 9px;
  }
  .intro-stamp-title {
    font-size: 21px;
    left: 9px;
    right: 9px;
    bottom: 9px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .intro-overlay {
    display: none;
  }
}