.spinner {
  position: absolute;
  top: 50%;
  left: 50%;
  z-index: 1;
  height: 40px;
  width: 40px;
  transform: translate(-50%, -50%);
}

[class^="ball-"] {
  position: absolute;
  display: block;
  left: 30px;
  width: 12px;
  height: 12px;
  border-radius: 6px;
  transition: all 0.5s;
  animation: circleRotate 4s both infinite;
  transform-origin: 0 250% 0;
}

@keyframes circleRotate {
  0% {
    transform: rotate(0deg);
  }
  100% {
    transform: rotate(1440deg);
  }
}
.ball-1 {
  z-index: -1;
  background-color: #f15a29;
  animation-timing-function: cubic-bezier(0.5, 0.3, 0.9, 0.9);
}

.ball-2 {
  z-index: -2;
  background-color: #f4792f;
  animation-timing-function: cubic-bezier(0.5, 0.6, 0.9, 0.9);
}

.ball-3 {
  z-index: -3;
  background-color: #f79437;
  animation-timing-function: cubic-bezier(0.5, 0.9, 0.9, 0.9);
}

.ball-4 {
  z-index: -4;
  background-color: #fbb040;
  animation-timing-function: cubic-bezier(0.5, 1.2, 0.9, 0.9);
}

.ball-5 {
  z-index: -5;
  background-color: #e1b73e;
  animation-timing-function: cubic-bezier(0.5, 1.5, 0.9, 0.9);
}

.ball-6 {
  z-index: -6;
  background-color: #c8bd3d;
  animation-timing-function: cubic-bezier(0.5, 1.8, 0.9, 0.9);
}

.ball-7 {
  z-index: -7;
  background-color: #acc23d;
  animation-timing-function: cubic-bezier(0.5, 2.1, 0.9, 0.9);
}

.ball-8 {
  z-index: -8;
  background-color: #8dc63f;
  animation-timing-function: cubic-bezier(0.5, 2.4, 0.9, 0.9);
}