html, body {
  margin: 0;
  overflow: hidden;
}

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ffffff;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.stage {
  padding: clamp(6px, 2.4vw, 16px);
}

@property --glow {
  syntax: "<length>";
  inherits: false;
  initial-value: 0px;
}
.badge {
  display: inline-block;
  border: 2px solid #2f6df6;
  border-radius: 999px;
  padding: 12px 24px;
  font-weight: 700;
  font-size: clamp(13px, 3.6vw, 15px);
  line-height: 1;
  font-family: inherit;
  color: #17141a;
  background: #ffffff;
  box-shadow: 0 0 var(--glow) 0 rgba(47, 109, 246, 0.55);
}

.badge.is-demo {
  animation: glow 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

@keyframes glow {
  0%, 100% {
    --glow: 0px;
  }
  50% {
    --glow: 16px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .badge.is-demo {
    animation: none;
    --glow: 8px;
  }
}