Webleb - HTML UI Elements -

#envelope {
  margin: 150px;
  position: relative;
  width: 280px;
  height: 180px;
  border-bottom-left-radius: 6px;
  border-bottom-right-radius: 6px;
  margin-left: auto;
  margin-right: auto;
  top: 150px;
  background-color: #f9c5c8;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
}

.front {
  position: absolute;
  width: 0;
  height: 0;
  z-index: 3;
}

.flap {
  border-left: 140px solid transparent;
  border-right: 140px solid transparent;
  border-bottom: 82px solid transparent;
  border-top: 98px solid #ff3333;
  transform-origin: top;
  pointer-events: none;
}

.pocket {
  border-left: 140px solid #ff9999;
  border-right: 140px solid #ff9999;
  border-bottom: 90px solid #fd8787;
  border-top: 90px solid transparent;
  border-bottom-left-radius: 6px;
  border-bottom-right-radius: 6px;
}

.letter {
  position: relative;
  background-color: #f9c5c8;
  width: 90%;
  margin-left: auto;
  margin-right: auto;
  height: 90%;
  top: 5%;
  border-radius: 6px;
  box-shadow: 0 2px 26px rgba(0, 0, 0, 0.12);
}

.letter:after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  background-image: linear-gradient(180deg, rgba(255, 255, 255, 0) 25%, rgba(239, 215, 239, 0.7) 55%, #eed7ef 100%);
}

.words {
  position: absolute;
  left: 10%;
  width: 80%;
  height: 14%;
  background-color: #fdb7ba;
}

.words.line1 {
  top: 15%;
  width: 20%;
  height: 7%;
}

.words.line2 {
  top: 30%;
}

.words.line3 {
  top: 50%;
}

.words.line4 {
  top: 70%;
}

.open .flap {
  transform: rotateX(180deg);
  transition: transform 0.4s ease, z-index 0.6s;
  z-index: 1;
}

.close .flap {
  transform: rotateX(0deg);
  transition: transform 0.4s 0.6s ease, z-index 1s;
  z-index: 5;
}

.close .letter {
  transform: translateY(0px);
  transition: transform 0.4s ease, z-index 1s;
  z-index: 1;
}

.open .letter {
  transform: translateY(-60px);
  transition: transform 0.4s 0.6s ease, z-index 0.6s;
  z-index: 2;
}

.hearts {
  position: absolute;
  top: 90px;
  left: 0;
  right: 0;
  z-index: 2;
}

.heart {
  position: absolute;
  bottom: 0;
  right: 10%;
  pointer-events: none;
}

.heart:before,
.heart:after {
  position: absolute;
  content: "";
  left: 50px;
  top: 0;
  width: 50px;
  height: 80px;
  background: #D00000;
  border-radius: 50px 50px 0 0;
  transform: rotate(-45deg);
  transform-origin: 0 100%;
  pointer-events: none;
}

.heart:after {
  left: 0;
  transform: rotate(45deg);
  transform-origin: 100% 100%;
}

.close .heart {
  opacity: 0;
  -webkit-animation: none;
          animation: none;
}

.a1 {
  left: 20%;
  transform: scale(0.6);
  opacity: 1;
  -webkit-animation: slideUp 4s linear 1, sideSway 2s ease-in-out 4 alternate;
  -moz-animation: slideUp 4s linear 1, sideSway 2s ease-in-out 4 alternate;
  -webkit-animation-fill-mode: forwards;
          animation-fill-mode: forwards;
  -webkit-animation-delay: 0.7s;
          animation-delay: 0.7s;
}

.a2 {
  left: 55%;
  transform: scale(1);
  opacity: 1;
  -webkit-animation: slideUp 5s linear 1, sideSway 4s ease-in-out 2 alternate;
  -moz-animation: slideUp 5s linear 1, sideSway 4s ease-in-out 2 alternate;
  -webkit-animation-fill-mode: forwards;
          animation-fill-mode: forwards;
  -webkit-animation-delay: 0.7s;
          animation-delay: 0.7s;
}

.a3 {
  left: 10%;
  transform: scale(0.8);
  opacity: 1;
  -webkit-animation: slideUp 7s linear 1, sideSway 2s ease-in-out 6 alternate;
  -moz-animation: slideUp 7s linear 1, sideSway 2s ease-in-out 6 alternate;
  -webkit-animation-fill-mode: forwards;
          animation-fill-mode: forwards;
  -webkit-animation-delay: 0.7s;
          animation-delay: 0.7s;
}

@-webkit-keyframes slideUp {
  0% {
    top: 0;
  }
  100% {
    top: -600px;
  }
}
@keyframes slideUp {
  0% {
    top: 0;
  }
  100% {
    top: -600px;
  }
}
@-webkit-keyframes sideSway {
  0% {
    margin-left: 0px;
  }
  100% {
    margin-left: 50px;
  }
}
@keyframes sideSway {
  0% {
    margin-left: 0px;
  }
  100% {
    margin-left: 50px;
  }
}
body {
  background-color: #f7d9da;
}

.envlope-wrapper {
  height: 380px;
}

.reset {
  text-align: center;
}

.reset button {
  font-weight: 800;
  font-style: normal;
  transition: all 0.1s linear;
  -webkit-appearance: none;
  background-color: transparent;
  border: solid 2px #ff5757;
  border-radius: 4px;
  color: #ff5757;
  display: inline-block;
  font-size: 14px;
  text-transform: uppercase;
  margin: 5px;
  padding: 10px;
  line-height: 1em;
  text-decoration: none;
  min-width: 120px;
  cursor: pointer;
}

.reset button:hover {
  background-color: #fc9d9d;
  color: #a10000;
}

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