.btn {
  border-right: 1px solid #ff758f;
  border-bottom: 1px solid #ff758f;
  border-top: 1px solid transparent;
  border-left: 1px solid transparent;
  outline: none;
  background: #f8f9fa;
  font-size: 17px;
  padding: 1em 2em;
  border-radius: .5em;
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow: hidden;
  transition: all .5s;
  z-index: 1;
}

.btn:hover {
  color: #212529;
  border-right: 1px solid transparent;
  border-bottom: 1px solid transparent;
  border-top: 1px solid #ff758f;
  border-left: 1px solid #ff758f;
  box-shadow: 1px 1px 0 #f8f9fa,
             2px 2px 0 #e9ecef,
             3px 3px 0 #fff0f3,
             4px 4px 0 #ffb3c1,
             5px 5px 0 #ff4d6d,
             6px 6px 0 #6c757d,
             7px 7px 0 #a4133c,
             8px 8px 0 #800f2f,
             9px 9px 0 #212529;
}

.btn:active {
  transition: 0s;
  transform: scale(.93);
}

.btn::before,
.btn::after {
  left: 0;
  content: '';
  position: absolute;
  background: #ffccd5;
  z-index: -1;
}

.btn::before {
  width: 0;
  height: 10%;
  transition: width .5s;
}

.btn:hover::before {
  width: 100%;
}

.btn::after {
  width: 100%;
  height: 0;
  border-radius: 100%;
  transition: all .5s .2s;
}

.btn:hover::after {
  height: 100%;
  border-radius: 0;
}