@keyframes flicker {
  0% {
    opacity: 1;
  }
  50% {
    opacity: 0.8;
  }
  100% {
    opacity: 1;
  }
}

.wisp {
  position: absolute;
  width: 1rem;
  height: 1rem;
  background-color: rgba(255, 255, 255, 0.1);
  border-radius: 50%;
  box-shadow: 0 0 2rem rgba(255, 255, 255, 0.2);
  animation: wisp-animation var(--duration, 30s) infinite ease-in-out;
}

@keyframes wisp-animation {
  0% {
    transform: translate(var(--startX, 0), var(--startY, 0))
      scale(var(--scaleStart, 1));
    opacity: var(--opacityStart, 0.5);
  }
  100% {
    transform: translate(var(--endX, 10vw), var(--endY, -50vh))
      scale(var(--scaleEnd, 1));
    opacity: var(--opacityEnd, 1);
  }
}