.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;
}

.estimator-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-dimmed);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  display: flex;
  align-items: center;
  gap: 0.3rem;
}

.label-sub {
  font-size: 0.65rem;
  color: var(--text-base);
  opacity: 0.35;
  font-weight: 400;
  text-transform: none;
  letter-spacing: 0;
}

.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);
}

.input-row {
  display: flex;
  gap: 0.75rem;
  align-items: flex-end;
}

.input-group {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.input-label {
  font-size: 0.75rem;
  color: var(--text-dimmed);
  font-weight: 600;
}

.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: 2.2rem;
  padding: 0.5rem 0.4rem;
  border: none;
  background: transparent;
  color: var(--text-dimmed);
  font-size: 0.8125rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.15s ease;
  user-select: none;
}

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

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

.chip-group {
  display: flex;
  gap: 0.25rem;
  background: var(--bg-page);
  padding: 0.25rem;
  border-radius: 2rem;
  border: 1px solid var(--border-base);
}

.chip {
  flex: 1;
  padding: 0.3rem 0.4rem;
  border: none;
  border-radius: 1.5rem;
  font-size: 0.7rem;
  font-weight: 600;
  cursor: pointer;
  background: transparent;
  color: var(--text-dimmed);
  transition: all 0.2s ease;
  white-space: nowrap;
}

.chip:hover {
  color: var(--text-base);
}

.chip.active {
  background: var(--accent);
  color: var(--text-on-primary, #fff);
}

.calc-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  width: 100%;
  padding: 0.7rem;
  border: none;
  border-radius: 2rem;
  background: var(--accent);
  color: var(--text-on-primary, #fff);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: 0 2px 12px rgba(99, 102, 241, 0.25);
}

.calc-btn:hover {
  opacity: 0.9;
  transform: translateY(-1px);
  box-shadow: 0 4px 16px rgba(99, 102, 241, 0.35);
}

.calc-btn:active {
  transform: scale(0.97);
}

.result-card {
  background: var(--bg-page);
  border: 1px solid var(--border-base);
  border-radius: 1rem;
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.875rem;
  animation: fade-slide-in 0.3s ease;
}

.result-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--accent);
  font-size: 0.8125rem;
  font-weight: 700;
}

.gauge-wrap {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.gauge-track {
  width: 100%;
  height: 14px;
  background: var(--border-base);
  border-radius: 7px;
  overflow: hidden;
}

.gauge-fill {
  height: 100%;
  border-radius: 6px;
  transition: width 0.6s ease, background 0.6s ease;
}

.gauge-marks {
  display: flex;
  justify-content: space-between;
  padding: 0 0.1rem;
}

.gauge-mark {
  font-size: 0.6rem;
  font-weight: 700;
  color: var(--text-base);
  opacity: 0.4;
}

.gauge-mark.gauge-danger {
  color: var(--color-danger, #ef4444);
  opacity: 0.9;
  font-weight: 800;
}

.gauge-mark.gauge-warning {
  color: var(--color-warning, #f59e0b);
  opacity: 0.85;
  font-weight: 800;
}

.gauge-mark.gauge-ok {
  color: var(--color-success, #22c55e);
  opacity: 0.85;
  font-weight: 800;
}

.charge-stats {
  display: flex;
  gap: 0.5rem;
}

.charge-stat {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
}

.stat-value {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--text-base);
  letter-spacing: -0.02em;
}

.stat-label {
  font-size: 0.6rem;
  font-weight: 600;
  color: var(--text-dimmed);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  text-align: center;
}

.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);
  line-height: 1.4;
  opacity: 0.85;
}

.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);
  line-height: 1.5;
  opacity: 0.85;
}

@keyframes fade-slide-in {
  from {
    opacity: 0;
    transform: translateY(-6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

  .input-row {
    flex-direction: column;
    gap: 0.5rem;
  }

  .charge-stats {
    flex-wrap: wrap;
  }

  .charge-stat {
    min-width: 30%;
  }
}