.tool-main-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 1.25rem;
  max-width: 400px;
  margin: 0 auto;
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
  box-shadow: var(--shadow-base);
  position: relative;
  overflow: hidden;
}

.converter-panel {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  position: relative;
  z-index: 1;
}

.panel-section {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.section-label {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-base);
  opacity: 0.7;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.movement-select {
  width: 100%;
  padding: 0.65rem 0.75rem;
  background: var(--bg-page);
  border: 1px solid var(--border-base);
  border-radius: 0.75rem;
  color: var(--text-base);
  font-size: 0.875rem;
  cursor: pointer;
  transition: border-color 0.2s;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24'%3E%3Cpath fill='%23888' d='M7 10l5 5 5-5z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0.75rem center;
  padding-right: 2rem;
}

.movement-select:focus {
  outline: none;
  border-color: var(--accent);
}

.stepper-wrap {
  display: flex;
  align-items: center;
  background: var(--bg-page);
  border: 1px solid var(--border-base);
  border-radius: 0.75rem;
  overflow: hidden;
  transition: border-color 0.2s;
}

.stepper-wrap:focus-within {
  border-color: var(--accent);
}

.stepper-input {
  width: 100%;
  padding: 0.6rem 0.25rem;
  border: none;
  background: transparent;
  color: var(--text-base);
  font-size: 0.875rem;
  text-align: center;
  font-variant-numeric: tabular-nums;
  box-sizing: border-box;
  -moz-appearance: textfield;
}

.stepper-input::-webkit-inner-spin-button,
.stepper-input::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.stepper-input:focus {
  outline: none;
}

.stepper-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 3rem;
  padding: 0.5rem;
  border: none;
  background: transparent;
  color: var(--text-base);
  opacity: 0.5;
  font-size: 0.75rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.15s ease;
  user-select: none;
}

.stepper-btn:hover {
  background: var(--bg-page);
  color: var(--accent);
  opacity: 1;
}

.stepper-btn:active {
  background: var(--border-base);
  transform: scale(0.95);
}

.result-card {
  background: var(--bg-page);
  border: 1px solid var(--border-base);
  border-radius: 1rem;
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.result-grid {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.result-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.1rem;
}

.result-value {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--accent);
  letter-spacing: -0.03em;
  line-height: 1;
  font-variant-numeric: tabular-nums;
}

.result-unit {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-base);
  opacity: 0.6;
  text-transform: uppercase;
}

.result-label {
  font-size: 0.65rem;
  font-weight: 600;
  color: var(--text-base);
  opacity: 0.5;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-top: 0.2rem;
}

.result-divider {
  width: 1px;
  height: 4rem;
  background: var(--border-base);
  flex-shrink: 0;
}

.impact-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-base);
  border-radius: 0.875rem;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.impact-header {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-base);
  opacity: 0.7;
}

.impact-result {
  display: flex;
  align-items: baseline;
  gap: 0.3rem;
}

.impact-value {
  font-size: 2rem;
  font-weight: 800;
  color: var(--color-warning, #f59e0b);
  letter-spacing: -0.02em;
  line-height: 1;
}

.impact-unit {
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--text-base);
  opacity: 0.6;
}

.impact-note {
  font-size: 0.75rem;
  color: var(--text-base);
  opacity: 0.6;
  line-height: 1.4;
  margin: 0;
}

.steps-section {
  display: flex;
  flex-direction: column;
  gap: 0.625rem;
  padding: 1rem 1.125rem;
  background: var(--bg-page);
  border-radius: 0.875rem;
  border: 1px solid var(--border-base);
}

.step-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.step-marker {
  width: 1.375rem;
  height: 1.375rem;
  border-radius: 50%;
  background: var(--accent);
  color: var(--text-on-primary, #fff);
  font-size: 0.6875rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.step-text {
  font-size: 0.8125rem;
  color: var(--text-base);
  opacity: 0.85;
  line-height: 1.4;
}

.tip-row {
  display: flex;
  gap: 0.5rem;
  padding: 0.75rem 1rem;
  background: var(--bg-page);
  border-radius: 0.75rem;
  border: 1px solid var(--border-base);
}

.tip-icon {
  flex-shrink: 0;
  margin-top: 0.1rem;
  color: var(--accent);
}

.tip-text {
  font-size: 0.8rem;
  color: var(--text-base);
  opacity: 0.85;
  line-height: 1.5;
}

@media (max-width: 520px) {
  .tool-main-card {
    padding: 1rem;
    gap: 1.25rem;
  }

  .result-value {
    font-size: 1.75rem;
  }
}