.sk-spinner-wrapper {
  position: fixed;
  top: 50%;
  left: 50%;
  margin-top: -20px;
  margin-left: -20px;
}
.sk-spinner-double-bounce.sk-spinner {
  width: 40px;
  height: 40px;
  position: relative;
  margin: 0 auto;
}
.sk-spinner-double-bounce .sk-double-bounce1,
.sk-spinner-double-bounce .sk-double-bounce2 {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background-color: #333;
  opacity: 0.6;
  position: absolute;
  top: 0;
  left: 0;
  -webkit-animation: sk-doubleBounce 2s infinite ease-in-out;
  animation: sk-doubleBounce 2s infinite ease-in-out;
}
.sk-spinner-double-bounce .sk-double-bounce2 {
  -webkit-animation-delay: -1s;
  animation-delay: -1s;
}
@-webkit-keyframes sk-doubleBounce {
  0%,
  100% {
    -webkit-transform: scale(0);
    transform: scale(0);
  }
  50% {
    -webkit-transform: scale(1);
    transform: scale(1);
  }
}
@keyframes sk-doubleBounce {
  0%,
  100% {
    -webkit-transform: scale(0);
    transform: scale(0);
  }
  50% {
    -webkit-transform: scale(1);
    transform: scale(1);
  }
}