@keyframes spinner {
  0% {
    background: #ff9100;
  }

  12.5% {
    background: #ff9100;
  }

  12.625% {
    background: #3f51b5;
  }

  100% {
    background: #3f51b5;
  }
}

.spinner div {
  position: absolute;
  width: 40px;
  height: 40px;
  background: #3f51b5;
  animation: spinner 1s linear infinite;
}

.spinner-wrapper {
  width: 200px;
  height: 100%;
  display: block;
  overflow: hidden;
  background: #ffffff;
  margin: auto;
}

.spinner {
  width: 100%;
  height: 100%;
  position: relative;
  transform: translateZ(0) scale(1);
  backface-visibility: hidden;
  transform-origin: 0 0;
  /* see note above */
}

.spinner div {
  box-sizing: content-box;
}