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.custom-btn {
  width: 130px;
  height: 40px;
  color: #fff;
  border-radius: 5px;
  padding: 10px 25px;
  font-family: 'Lato', sans-serif;
  font-weight: 500;
  background: transparent;
  cursor: pointer;
  transition: all 0.3s ease;
  position: relative;
  display: inline-block;
   box-shadow:inset 2px 2px 2px 0px rgba(255,255,255,.5),
   7px 7px 20px 0px rgba(0,0,0,.1),
   4px 4px 5px 0px rgba(0,0,0,.1);
  outline: none;
}
.btn-12{
  position: relative;
  right: 20px;
  bottom: 20px;
  border:none;
  box-shadow: none;
  width: 130px;
  height: 40px;
  line-height: 42px;
  -webkit-perspective: 230px;
  perspective: 230px;
}
.btn-12 span {
  background: rgb(0,172,238);
background: linear-gradient(0deg, rgba(0,172,238,1) 0%, rgba(2,126,251,1) 100%);
  display: block;
  position: absolute;
  width: 130px;
  height: 40px;
  box-shadow:inset 2px 2px 2px 0px rgba(255,255,255,.5),
   7px 7px 20px 0px rgba(0,0,0,.1),
   4px 4px 5px 0px rgba(0,0,0,.1);
  border-radius: 5px;
  margin:0;
  text-align: center;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
  -webkit-transition: all .3s;
  transition: all .3s;
}
.btn-12 span:nth-child(1) {
  box-shadow:
   -7px -7px 20px 0px #fff9,
   -4px -4px 5px 0px #fff9,
   7px 7px 20px 0px #0002,
   4px 4px 5px 0px #0001;
  -webkit-transform: rotateX(90deg);
  -moz-transform: rotateX(90deg);
  transform: rotateX(90deg);
  -webkit-transform-origin: 50% 50% -20px;
  -moz-transform-origin: 50% 50% -20px;
  transform-origin: 50% 50% -20px;
}
.btn-12 span:nth-child(2) {
  -webkit-transform: rotateX(0deg);
  -moz-transform: rotateX(0deg);
  transform: rotateX(0deg);
  -webkit-transform-origin: 50% 50% -20px;
  -moz-transform-origin: 50% 50% -20px;
  transform-origin: 50% 50% -20px;
}
.btn-12:hover span:nth-child(1) {
  box-shadow:inset 2px 2px 2px 0px rgba(255,255,255,.5),
   7px 7px 20px 0px rgba(0,0,0,.1),
   4px 4px 5px 0px rgba(0,0,0,.1);
  -webkit-transform: rotateX(0deg);
  -moz-transform: rotateX(0deg);
  transform: rotateX(0deg);
}
.btn-12:hover span:nth-child(2) {
  box-shadow:inset 2px 2px 2px 0px rgba(255,255,255,.5),
   7px 7px 20px 0px rgba(0,0,0,.1),
   4px 4px 5px 0px rgba(0,0,0,.1);
 color: transparent;
  -webkit-transform: rotateX(-90deg);
  -moz-transform: rotateX(-90deg);
  transform: rotateX(-90deg);
}

External CSS

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