style.css

:root {
  scroll-behavior: smooth;
  display: grid;
  place-items: center;
  background-color: #303030;
}

.sk-cube-grid {
  align-self: center;
  width: 8rem;
  height: 8rem;
  margin: 100px auto;
}

.sk-cube-grid .sk-cube {
  width: 33%;
  height: 33%;
  background-color: #fccfa8;
  float: left;
  -webkit-animation: sk-cubeGridScaleDelay 1.3s infinite ease-in-out;
  animation: sk-cubeGridScaleDelay 1.3s infinite ease-in-out;
}

.sk-cube-grid .sk-cube1 {
  -webkit-animation-delay: 0.2s;
  animation-delay: 0.2s;
}

.sk-cube-grid .sk-cube2 {
  -webkit-animation-delay: 0.3s;
  animation-delay: 0.3s;
}

.sk-cube-grid .sk-cube3 {
  -webkit-animation-delay: 0.4s;
  animation-delay: 0.4s;
}

.sk-cube-grid .sk-cube4 {
  -webkit-animation-delay: 0.1s;
  animation-delay: 0.1s;
}

.sk-cube-grid .sk-cube5 {
  -webkit-animation-delay: 0.2s;
  animation-delay: 0.2s;
}

.sk-cube-grid .sk-cube6 {
  -webkit-animation-delay: 0.3s;
  animation-delay: 0.3s;
}

.sk-cube-grid .sk-cube7 {
  -webkit-animation-delay: 0s;
  animation-delay: 0s;
}

.sk-cube-grid .sk-cube8 {
  -webkit-animation-delay: 0.1s;
  animation-delay: 0.1s;
}

.sk-cube-grid .sk-cube9 {
  -webkit-animation-delay: 0.2s;
  animation-delay: 0.2s;
}

@-webkit-keyframes fadein {
  from {
    bottom: 0;
    opacity: 0;
  }

  to {
    bottom: 30px;
    opacity: 1;
  }
}

@keyframes fadein {
  from {
    bottom: 0;
    opacity: 0;
  }

  to {
    bottom: 30px;
    opacity: 1;
  }
}

@-webkit-keyframes sk-cubeGridScaleDelay {
  0%,
  70%,
  100% {
    -webkit-transform: scale3D(1, 1, 1);
    transform: scale3D(1, 1, 1);
  }

  35% {
    -webkit-transform: scale3D(0, 0, 1);
    transform: scale3D(0, 0, 1);
  }
}

@keyframes sk-cubeGridScaleDelay {
  0%,
  70%,
  100% {
    -webkit-transform: scale3D(1, 1, 1);
    transform: scale3D(1, 1, 1);
  }

  35% {
    -webkit-transform: scale3D(0, 0, 1);
    transform: scale3D(0, 0, 1);
  }
}