<div class="cbgp-dust" role="group" aria-label="Subscription tiers">
  <button type="button">Starter</button>
  <button type="button" class="is-on">Plus</button>
  <button type="button">Team</button>
</div>

.cbgp-dust {
  position: relative; display: inline-flex;
  padding: 6px;
  background: #050810;
  border: 1px solid rgba(255,255,255,0.06);
  border-radius: 14px;
  overflow: hidden;
  isolation: isolate;
}
.cbgp-dust::before {
  content: '';
  position: absolute; inset: -50%;
  background:
    radial-gradient(circle 70px at 20% 30%, rgba(0,255,224,0.55), transparent 60%),
    radial-gradient(circle 60px at 60% 70%, rgba(255,90,241,0.5),  transparent 60%),
    radial-gradient(circle 80px at 90% 40%, rgba(255,212,121,0.45), transparent 60%),
    radial-gradient(circle 50px at 30% 80%, rgba(0,184,232,0.5),    transparent 60%);
  filter: blur(20px);
  z-index: -1;
  animation: cbgp-dust-drift 12s ease-in-out infinite;
}
.cbgp-dust::after {
  content: '';
  position: absolute; inset: 0;
  background:
    repeating-linear-gradient(45deg,
      rgba(255,255,255,0.012) 0 1px,
      transparent 1px 3px),
    rgba(5,8,16,0.5);
  z-index: -1;
}
@keyframes cbgp-dust-drift {
  0%, 100% { transform: translate(0, 0) rotate(0deg); }
  33%      { transform: translate(-6%, 4%) rotate(2deg); }
  66%      { transform: translate(4%, -3%) rotate(-2deg); }
}
.cbgp-dust button {
  padding: 11px 22px;
  border: 0; cursor: pointer;
  background: transparent;
  color: rgba(220,225,230,0.7);
  font: 700 12px/1 ui-monospace, monospace;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  border-radius: 10px;
  position: relative;
  transition: background 0.25s, color 0.25s, transform 0.3s;
}
.cbgp-dust button:hover {
  color: #fff;
  background: rgba(255,255,255,0.06);
  transform: translateY(-1px);
}
.cbgp-dust button.is-on {
  background: rgba(8,10,18,0.6);
  color: #fff;
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.08);
}
.cbgp-dust button:focus-visible { outline: 2px solid #00ffe0; outline-offset: 3px; }
@media (prefers-reduced-motion: reduce) {
  .cbgp-dust::before { animation: none !important; }
}