Moon Phase Night Card

<!-- Moon Phase Night Card (a dark disc slides across the moon, slowly) -->
<div class="nuda-wa2-moon-phase" role="img" aria-label="Moon cycling through its phases over a starfield">
  <span class="nuda-wa2-moon-phase__stars"></span>
  <span class="nuda-wa2-moon-phase__moon">
    <span class="nuda-wa2-moon-phase__shadow"></span>
  </span>
</div>

.nuda-wa2-moon-phase {
  position: relative;
  width: 100%;
  max-width: 200px;
  height: 130px;
  border-radius: 14px;
  overflow: hidden;
  background: radial-gradient(ellipse at 50% 20%,#12121c,#09090b 75%);
}

.nuda-wa2-moon-phase__stars {
  position: absolute;
  inset: 0;
  background-image: radial-gradient(1px 1px at 15% 70%,#fafafa,transparent),radial-gradient(1px 1px at 75% 60%,#fafafa,transparent),radial-gradient(1px 1px at 30% 85%,#fafafa,transparent),radial-gradient(1px 1px at 88% 80%,#fafafa,transparent),radial-gradient(1px 1px at 55% 90%,#fafafa,transparent);
  opacity: .6;
}

.nuda-wa2-moon-phase__moon {
  position: absolute;
  top: 30px;
  left: 50%;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  transform: translateX(-50%);
  background: radial-gradient(circle at 35% 35%,#fafafa,#d8d8d0 55%,#b8b8ac 100%);
  box-shadow: 0 0 18px rgba(250,250,250,.25);
  overflow: hidden;
}

.nuda-wa2-moon-phase__moon::before,.nuda-wa2-moon-phase__moon::after {
  content: "";
  position: absolute;
  border-radius: 50%;
  background: rgba(0,0,0,.12);
}

.nuda-wa2-moon-phase__moon::before {
  width: 14px;
  height: 14px;
  top: 14px;
  left: 10px;
}

.nuda-wa2-moon-phase__moon::after {
  width: 9px;
  height: 9px;
  top: 32px;
  left: 30px;
}

.nuda-wa2-moon-phase__shadow {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: #09090b;
  will-change: transform;
  animation: _nuda-wa2moonPhaseCycle 18s ease-in-out infinite;
}

@keyframes _nuda-wa2moonPhaseCycle {
  0% {
    transform: translateX(-100%);
  }
  50% {
    transform: translateX(0);
  }
  100% {
    transform: translateX(100%);
  }
}

@media (prefers-reduced-motion:reduce) {
  .nuda-wa2-moon-phase__shadow {
    animation: none;
    transform: translateX(-30%);
  }
}