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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #ff4d1f;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.btn {
  box-sizing: border-box;
  position: relative;
  width: 240px;
  height: 64px;
  border: none;
  border-radius: 999px;
  background: #bcded4;
  color: #17141a;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  font-weight: 700;
  font-size: 18px;
  cursor: pointer;
}

.btn__label {
  position: relative;
  z-index: 1;
}

.btn::before,
.btn::after {
  content: "";
  position: absolute;
  top: 50%;
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: #bcded4;
  transform: translateY(-50%) scale(0.3);
}

.btn::before {
  left: -4px;
}

.btn::after {
  right: -4px;
}

.btn:hover::before {
  transform: translateY(-50%) scale(1.25) translateX(-8px);
}

.btn:hover::after {
  transform: translateY(-50%) scale(1.25) translateX(8px);
}

.btn::before, .btn::after {
  transition: transform 300ms cubic-bezier(0.2, 1.4, 0.4, 1);
}

.btn:focus-visible {
  outline: 3px solid #17141a;
  outline-offset: 4px;
}

.stage.is-demo .btn::before {
  animation: blob-l 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}

.stage.is-demo .btn::after {
  animation: blob-r 2s cubic-bezier(0.2, 1.4, 0.4, 1) infinite;
}

@keyframes blob-l {
  0%, 12% {
    transform: translateY(-50%) scale(0.3);
  }
  40% {
    transform: translateY(-50%) scale(1.3) translateX(-8px);
  }
  68%, 82% {
    transform: translateY(-50%) scale(1.15) translateX(-4px);
  }
  100% {
    transform: translateY(-50%) scale(0.3);
  }
}
@keyframes blob-r {
  0%, 12% {
    transform: translateY(-50%) scale(0.3);
  }
  40% {
    transform: translateY(-50%) scale(1.3) translateX(8px);
  }
  68%, 82% {
    transform: translateY(-50%) scale(1.15) translateX(4px);
  }
  100% {
    transform: translateY(-50%) scale(0.3);
  }
}
@media (prefers-reduced-motion: reduce) {
  .stage.is-demo .btn::before, .stage.is-demo .btn::after {
    animation: none;
  }
}