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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #17141a;
  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: #fff7e6;
  color: #17141a;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  font-weight: 700;
  font-size: 17px;
  cursor: pointer;
  overflow: hidden;
}

.btn__track {
  display: flex;
  width: 200%;
  height: 100%;
  transition: transform 300ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.btn__cell {
  box-sizing: border-box;
  flex: 0 0 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  white-space: nowrap;
}

.btn__arrow {
  width: 20px;
  height: 20px;
  color: #ff4d1f;
}

.btn:hover .btn__track {
  transform: translateX(-50%);
}

.btn:focus-visible {
  outline: 3px solid #ffd23f;
  outline-offset: 4px;
}

.stage.is-demo .btn__track {
  animation: slide-in 2s cubic-bezier(0.2, 0.8, 0.2, 1) infinite;
}

@keyframes slide-in {
  0%, 18% {
    transform: translateX(0);
  }
  55%, 72% {
    transform: translateX(-50%);
  }
  88% {
    transform: translateX(-4%);
  }
  100% {
    transform: translateX(0);
  }
}
@media (prefers-reduced-motion: reduce) {
  .stage.is-demo .btn__track {
    animation: none;
    transform: translateX(-50%);
  }
}