.checkbox {
  display: inline-block;
  position: relative;
  cursor: pointer;
}

.checkbox__input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.checkbox__label {
  display: inline-block;
  padding-left: 30px;
  margin-bottom: 10px;
  position: relative;
  font-size: 16px;
  color: #fff;
  cursor: pointer;
  transition: all 0.6s cubic-bezier(0.23, 1, 0.320, 1);
}

.checkbox__custom {
  position: absolute;
  top: 0;
  left: 0;
  width: 20px;
  height: 20px;
  background: linear-gradient(#212121, #212121) padding-box,
              linear-gradient(145deg,#e81cff, #40c9ff) border-box;
  border: 2px solid transparent;
  transition: all 0.6s cubic-bezier(0.23, 1, 0.320, 1);
}

.checkbox__input:checked + .checkbox__label .checkbox__custom {
  background-image: linear-gradient(145deg,#e81cff, #40c9ff);
  transform: rotate(45deg) scale(0.8);
}

.checkbox__label:hover .checkbox__custom {
  transform: scale(1.2);
}