* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
h1 {
  font-size: 2em;
  color: #fff;
  padding: 0.5em;
}
:root {
}
body {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background: black;
}

.cubo {
  position: relative;
  width: 300px;
  height: 300px;
  transform-style: preserve-3d;
  transform: rotateX(-30deg);
  animation: girar 4s linear infinite;
}

@keyframes girar {
  0% {
    transform: rotateX(-30deg) rotateY(0deg);
  }
  100% {
    transform: rotateX(-30deg) rotateY(360deg);
  }
}

.lado {
  filter: blur(1px);
  border: 2px solid rgba(0, 217, 255, 0.274);
  animation: cambiar 1s ease-in-out infinite alternate;
  background: rgb(80, 184, 255);
  background: radial-gradient(
    circle,
    rgba(80, 184, 255, 1) 0%,
    rgba(0, 69, 255, 1) 100%
  );
}

@keyframes cambiar {
  0% {
    opacity: 0.7;
  }
  100% {
    opacity: 0.6;
  }
}

.cubo div {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  transform-style: preserve-3d;
}

.cubo div span {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  transform: rotateY(calc(90deg * var(--i))) translateZ(150px);
}

.arriba {
  position: absolute;
  top: 0;
  left: 0;
  width: 300px;
  height: 300px;
  transform: rotateX(90deg) translateZ(150px);
}

.abajo {
  position: absolute;
  top: 0;
  left: 0;
  width: 300px;
  height: 300px;
  transform: rotateX(90deg) translateZ(-150px);
}

.brillo {
  position: absolute;
  top: 0;
  left: 0;
  width: 300px;
  height: 300px;
  background: rgb(0, 174, 255);
  filter: blur(90px);
  transform: rotateX(90deg) translateZ(-200px);
  box-shadow: 0 0 300px rgb(0, 119, 255), 0 0 500px rgb(30, 191, 255),
    0 0 700px rgb(11, 152, 207), 0 0 800px rgb(11, 152, 207);
  animation: cambiar 1s linear infinite alternate;
}