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

.stage {
  box-sizing: border-box;
  min-height: 100vh;
  display: grid;
  place-items: center;
  margin: 0;
  background: #eaf6f1;
  font-family: -apple-system, "Segoe UI", "Noto Sans KR", sans-serif;
  padding: clamp(8px, 4vw, 24px);
}

.controls {
  box-sizing: border-box;
  width: clamp(220px, 78vw, 280px);
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.controls__field {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.controls__label {
  color: #475569;
  font-weight: 600;
  font-size: 11px;
  line-height: 1.4;
  font-family: inherit;
}

.controls__input {
  box-sizing: border-box;
  width: 100%;
  border: 1.5px solid #e2e8f0;
  border-radius: 8px;
  background: #ffffff;
  color: #17141a;
  padding: 8px 12px;
  font-weight: 500;
  font-size: 13px;
  line-height: 1.4;
  font-family: inherit;
  outline: none;
  animation: ringPulse 2s ease-out infinite;
}

.controls__input::placeholder {
  color: #475569;
  opacity: 0.65;
}

.controls__btn {
  border: 0;
  border-radius: 12px;
  background: #2f6df6;
  color: #ffffff;
  padding: 8px 20px;
  font-weight: 700;
  font-size: 13px;
  line-height: 1;
  font-family: inherit;
  box-shadow: 0 6px 14px rgba(47, 109, 246, 0.28);
  animation: btnDarken 2s ease-out infinite;
}

@keyframes ringPulse {
  0%, 60%, 100% {
    border-color: #e2e8f0;
    box-shadow: none;
  }
  25% {
    border-color: #2f6df6;
    box-shadow: 0 0 0 4px rgba(47, 109, 246, 0.18);
  }
}
@keyframes btnDarken {
  0%, 60%, 100% {
    transform: translateY(0);
    background: #2f6df6;
    box-shadow: 0 6px 14px rgba(47, 109, 246, 0.28);
  }
  25% {
    transform: translateY(-1px);
    background: #7386ba;
    box-shadow: 0 10px 18px rgba(29, 78, 216, 0.34);
  }
}
@media (max-width: 340px), (max-height: 220px) {
  .controls {
    gap: 8px;
  }
  .controls__input {
    padding: 4px 8px;
  }
  .controls__btn {
    padding: 4px 16px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .controls__input, .controls__btn {
    animation: none !important;
    transform: none;
  }
  .controls__input {
    border-color: #e2e8f0;
    box-shadow: none;
  }
  .controls__btn {
    background: #2f6df6;
  }
}