.calc {
  max-width: 800px;
  margin: 0 auto;
  background: var(--color-white);
  border-radius: var(--radius-lg);
  padding: clamp(24px, 4vw, 48px);
  box-shadow: var(--shadow-lg);
}

/* Progress */
.calc__progress {
  margin-bottom: 32px;
}

.calc__progress-bar {
  height: 4px;
  background: #e2e8f0;
  border-radius: 2px;
  margin-bottom: 16px;
  overflow: hidden;
}

.calc__progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), var(--color-accent));
  border-radius: 2px;
  width: 20%;
  transition: width var(--transition-slow);
}

.calc__steps-indicator {
  display: flex;
  justify-content: space-between;
}

.calc__step-dot {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: #e2e8f0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--fs-small);
  font-weight: var(--fw-semibold);
  color: var(--color-text-muted);
  transition: all var(--transition);
}

.calc__step-dot.active {
  background: var(--color-primary);
  color: var(--color-white);
}

.calc__step-dot.completed {
  background: var(--color-success);
  color: var(--color-white);
}

/* Panels */
.calc__panel {
  display: none;
}

.calc__panel.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.calc__panel-title {
  font-size: var(--fs-h3);
  margin-bottom: 24px;
  text-align: center;
}

/* Options */
.calc__options {
  gap: 16px;
}

.calc__options--row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.calc__option {
  cursor: pointer;
}

.calc__option input[type="radio"] {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.calc__option-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  padding: 24px 16px;
  border: 2px solid #e2e8f0;
  border-radius: var(--radius);
  text-align: center;
  font-weight: var(--fw-medium);
  transition: all var(--transition);
}

.calc__option-card:hover {
  border-color: var(--color-primary-light);
  background: rgba(0, 82, 181, 0.04);
}

.calc__option input:checked + .calc__option-card {
  border-color: var(--color-primary);
  background: rgba(0, 82, 181, 0.08);
  box-shadow: 0 0 0 3px rgba(0, 82, 181, 0.15);
}

.calc__option-card small {
  display: block;
  color: var(--color-text-muted);
  font-size: var(--fs-xs);
  font-weight: var(--fw-regular);
}

.calc__option--sm .calc__option-card {
  padding: 14px 20px;
  flex-direction: column;
  gap: 4px;
}

.calc__options--row .calc__option {
  flex: 1;
  min-width: 120px;
}

/* Groups */
.calc__group {
  margin-bottom: 24px;
}

.calc__group-label {
  font-weight: var(--fw-semibold);
  color: var(--color-text);
  margin-bottom: 12px;
  font-size: var(--fs-body);
}

/* Sliders */
.calc__slider-group {
  margin-bottom: 20px;
}

.calc__slider-label {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
  font-weight: var(--fw-medium);
}

.calc__slider-label output {
  font-size: 1.125rem;
  font-weight: var(--fw-bold);
  color: var(--color-primary);
  min-width: 40px;
  text-align: right;
}

.calc__slider {
  width: 100%;
  height: 8px;
  -webkit-appearance: none;
  appearance: none;
  background: #e2e8f0;
  border-radius: 4px;
  outline: none;
}

.calc__slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--color-primary);
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(0, 82, 181, 0.3);
  transition: all var(--transition);
}

.calc__slider::-webkit-slider-thumb:hover {
  transform: scale(1.15);
  box-shadow: 0 2px 12px rgba(0, 82, 181, 0.5);
}

.calc__slider::-moz-range-thumb {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--color-primary);
  cursor: pointer;
  border: none;
  box-shadow: 0 2px 8px rgba(0, 82, 181, 0.3);
}

.calc__volume {
  margin-top: 16px;
  padding: 16px;
  background: var(--color-light);
  border-radius: var(--radius);
  text-align: center;
  font-size: 1.0625rem;
}

.calc__volume strong {
  font-size: 1.5rem;
  color: var(--color-primary);
  margin: 0 4px;
}

/* Checkboxes */
.calc__checkboxes {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.calc__checkbox {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  padding: 10px 16px;
  border: 2px solid #e2e8f0;
  border-radius: var(--radius);
  font-size: var(--fs-small);
  font-weight: var(--fw-medium);
  transition: all var(--transition);
}

.calc__checkbox:hover {
  border-color: var(--color-primary-light);
}

.calc__checkbox input {
  display: none;
}

.calc__checkbox-mark {
  width: 20px;
  height: 20px;
  border: 2px solid #cbd5e1;
  border-radius: 4px;
  position: relative;
  transition: all var(--transition);
  flex-shrink: 0;
}

.calc__checkbox input:checked ~ .calc__checkbox-mark {
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.calc__checkbox input:checked ~ .calc__checkbox-mark::after {
  content: '';
  position: absolute;
  top: 2px;
  left: 6px;
  width: 5px;
  height: 10px;
  border: solid white;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}

.calc__checkbox input:checked ~ span:last-child {
  color: var(--color-primary);
}

/* Result */
.calc__result {
  text-align: center;
}

.calc__result-price {
  margin-bottom: 16px;
}

.calc__result-label {
  font-size: var(--fs-body);
  color: var(--color-text-muted);
  display: block;
  margin-bottom: 8px;
}

.calc__result-value {
  font-size: clamp(1.25rem, 2.5vw, 1.75rem);
  color: var(--color-text);
}

.calc__result-value strong {
  color: var(--color-primary);
  font-size: clamp(1.5rem, 3vw, 2.25rem);
}

.calc__result-disclaimer {
  font-size: var(--fs-small);
  color: var(--color-text-muted);
  font-style: italic;
  margin-bottom: 24px;
}

.calc__result-summary {
  text-align: left;
  padding: 16px;
  background: var(--color-light);
  border-radius: var(--radius);
  margin-bottom: 24px;
  font-size: var(--fs-small);
  line-height: 1.8;
}

.calc__result-form {
  border-top: 1px solid #e2e8f0;
  padding-top: 24px;
}

.calc__result-form-title {
  font-weight: var(--fw-semibold);
  margin-bottom: 16px;
  font-size: var(--fs-h3);
}

.calc__result-form-fields {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 16px;
}

.calc__result-form-fields .form-input,
.calc__result-form-fields .form-select {
  flex: 1;
  min-width: 180px;
}

/* Step Info */
.calc__step-info {
  text-align: center;
  color: var(--color-text-muted);
  font-size: var(--fs-small);
  margin-bottom: 8px;
  font-weight: var(--fw-medium);
}

/* Fixed Type Badge */
.calc__fixed-type {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 20px 32px;
  background: var(--color-white);
  border: 2px solid var(--color-primary);
  border-radius: 12px;
  margin: 0 auto 24px;
  width: 100%;
  max-width: 400px;
  text-align: center;
}

.calc__fixed-type-name {
  font-size: 1.25rem;
  font-weight: var(--fw-semibold);
  color: var(--color-text);
}

.calc__fixed-type-hint {
  font-size: var(--fs-small);
  color: var(--color-text-muted);
}

/* Summary Rows */
.calc__summary-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 0;
  border-bottom: 1px solid #e2e8f0;
}

.calc__summary-row:last-child {
  border-bottom: none;
}

.calc__summary-row span {
  color: var(--color-text-muted);
}

.calc__summary-row strong {
  color: var(--color-text);
  text-align: right;
}

/* Upload Hint */
.calc__upload-hint {
  background: var(--color-light);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 24px;
  text-align: center;
}

.calc__upload-hint p {
  font-size: var(--fs-small);
  color: var(--color-text-muted);
  margin-bottom: 16px;
  line-height: 1.6;
}

/* File Upload */
.calc__file-upload {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  cursor: pointer;
}

.calc__file-upload input[type="file"] {
  display: none;
}

.calc__file-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  background: var(--color-white);
  border: 2px dashed var(--color-primary);
  border-radius: var(--radius);
  color: var(--color-primary);
  font-weight: var(--fw-medium);
  font-size: var(--fs-small);
  transition: all var(--transition);
}

.calc__file-btn:hover {
  background: rgba(0, 82, 181, 0.05);
  border-style: solid;
}

.calc__file-name {
  font-size: var(--fs-xs);
  color: var(--color-success);
  font-weight: var(--fw-medium);
}

/* Navigation */
.calc__nav {
  display: flex;
  justify-content: space-between;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid #e2e8f0;
}