.envelope-screen {
  min-height: 100vh;
  min-height: 100svh;
  display: grid;
  place-items: center;
  padding: 110px 30px 70px;
  overflow: hidden;
}

.envelope-button {
  display: block;
  width: min(100%, 470px);
  padding: 0;
  border: 0;
  background: none;
  cursor: pointer;
  perspective: 1200px;
  -webkit-tap-highlight-color: transparent;
}

.envelope {
  position: relative;
  display: block;
  width: 100%;
  aspect-ratio: 26 / 17;
  transform: rotate(-4deg);
  transition: transform 350ms ease;
  isolation: isolate;
}

.envelope-back {
  position: absolute;
  inset: 0;
  background: #dfcbb1;
  border-radius: 3px;
  box-shadow: 0 3px 5px #65513b0a, 0 20px 48px #65513b18;
}

.envelope-letter {
  position: absolute;
  z-index: 1;
  left: 7%;
  top: 8%;
  width: 86%;
  height: 82%;
  padding: 4% 4% 9%;
  background: #fffdf8;
  box-shadow: 0 0 3px #65513b13;
}

.envelope-photo {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  height: 100%;
  padding: 6% 2%;
  background: #faf8f2;
}

.envelope-photo img:first-child { width: 35%; filter: brightness(1.16) contrast(.98) saturate(.94); }
.envelope-photo img:last-child { width: 48%; filter: brightness(1.09) contrast(.98) saturate(.94); }
.envelope-photo img { display: block; height: auto; }
.envelope-photo > span { align-self: center; color: #bfa69b; font: 24px Georgia, serif; }

.envelope-pocket { position: absolute; inset: 0; width: 100%; height: 100%; z-index: 3; }
.envelope-flap {
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 57.65%;
  z-index: 4;
  transform-origin: 50% 0;
  transition: transform 550ms cubic-bezier(.35, 0, .25, 1), z-index 0s 250ms;
}
.envelope-flap svg { display: block; width: 100%; height: 100%; overflow: visible; }
.envelope-seal {
  position: absolute;
  z-index: 5;
  left: 50%;
  top: 52%;
  width: 52px;
  height: 52px;
  display: grid;
  place-items: center;
  background: #c78f92;
  border: 1px solid #b77c7f;
  border-radius: 50%;
  box-shadow: inset 0 0 0 4px #d49fa2, 0 2px 3px #6a403521;
  color: #fff5e7;
  font: 32px Georgia, serif;
  transform: translate(-50%, -50%);
  transition: opacity 150ms, transform 180ms;
}

.envelope-cue {
  display: block;
  margin-top: 47px;
  font: italic 16px Georgia, serif;
  color: #8b7767;
  transition: opacity 200ms;
}

@media (hover: hover) {
  .envelope-button:not(:disabled):hover .envelope { transform: translateY(-5px) rotate(-2deg); }
}

.envelope-screen.is-opening { animation: envelope-away 450ms 850ms ease both; }
.is-opening .envelope { transform: rotate(0); }
.is-opening .envelope-seal { opacity: 0; transform: translate(-50%, -50%) scale(.8); }
.is-opening .envelope-flap { transform: rotateX(-180deg); z-index: 0; }
.is-opening .envelope-letter { animation: letter-out 650ms 300ms cubic-bezier(.2,.75,.25,1) both; }
.is-opening .envelope-cue { opacity: 0; }
.card-arriving { animation: card-arrive 650ms cubic-bezier(.2,.75,.25,1) both; }

@keyframes letter-out { to { transform: translateY(-57%) rotate(2deg); } }
@keyframes envelope-away { to { opacity: 0; transform: translateY(32px); } }
@keyframes card-arrive { from { opacity: 0; translate: 0 25px; } to { opacity: 1; translate: 0 0; } }

@media (max-width: 600px) {
  .envelope-screen { padding-inline: 32px; padding-bottom: 100px; }
  .envelope-seal { width: 43px; height: 43px; font-size: 28px; }
  .envelope-cue { margin-top: 38px; font-size: 15px; }
}

@media (prefers-reduced-motion: reduce) {
  .envelope-screen, .envelope *, .card-arriving { animation: none !important; transition: none !important; }
}