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);
}

.panel {
  width: 100%;
  max-width: 360px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.hint {
  margin: 0;
  padding: 0 8px;
  text-align: center;
  font-weight: 400;
  font-size: 11px;
  line-height: 1.4;
  color: rgba(23, 20, 26, 0.72);
}

.track {
  position: relative;
  width: 100%;
  height: 6px;
  border-radius: 999px;
  background: rgba(23, 20, 26, 0.18);
}

.fill {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  border-radius: 999px;
  background: #17141a;
  width: 0%;
  transition: width 600ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.knob {
  position: absolute;
  top: 50%;
  left: 0;
  width: 16px;
  height: 16px;
  margin-top: -8px;
  border-radius: 999px;
  background: #fff7e6;
  box-shadow: 0 6px 12px rgba(23, 20, 26, 0.32);
  transition: left 600ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.usageLine {
  margin: 0;
  font-weight: 700;
  font-size: 16px;
  color: #17141a;
}

.usageUnit {
  font-weight: 400;
  font-size: 11px;
  color: rgba(23, 20, 26, 0.7);
}

.estimate {
  margin: 0;
  padding: 4px 12px;
  border-radius: 999px;
  background: #17141a;
  color: #fff7e6;
  font-weight: 700;
  font-size: 12px;
  transition: background 600ms cubic-bezier(0.2, 0.8, 0.2, 1);
}

.estimate.is-contact {
  background: #c93000;
}

@media (max-width: 340px) {
  .panel {
    max-width: 280px;
    gap: 4px;
  }
  .hint {
    font-size: 9px;
  }
  .usageLine {
    font-size: 13px;
  }
  .estimate {
    font-size: 11px;
  }
}
@media (prefers-reduced-motion: reduce) {
  .fill,
  .knob,
  .estimate {
    transition: none;
  }
}