* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #c0392b;
  --primary-dark: #a93226;
  --primary-light: #e74c3c;
  --bg: #f8f9fa;
  --card: #ffffff;
  --text: #2c3e50;
  --text-light: #6c757d;
  --border: #dee2e6;
  --success: #27ae60;
  --error: #e74c3c;
  --radius: 12px;
  --shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}

.container {
  max-width: 640px;
  margin: 0 auto;
  padding: 20px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
header {
  text-align: center;
  padding: 32px 0 24px;
}

.logo-link {
  display: inline-block;
}

.logo-img {
  max-width: 180px;
  height: auto;
}

.logo-sub {
  display: block;
  font-size: 14px;
  color: var(--text-light);
  font-weight: 500;
}

/* Steps */
.step {
  background: var(--card);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  margin-bottom: 20px;
}

.step.hidden {
  display: none;
}

.step-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 8px;
}

.step-number {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--primary);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 16px;
  flex-shrink: 0;
}

.step-number.success-icon {
  background: var(--success);
  font-size: 20px;
}

.step-header h2 {
  font-size: 20px;
  font-weight: 600;
}

.step-desc {
  color: var(--text-light);
  font-size: 14px;
  margin-bottom: 20px;
  padding-left: 50px;
}

/* Forms */
.form-group {
  margin-bottom: 16px;
}

.form-group label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--text);
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1.5px solid var(--border);
  border-radius: 8px;
  font-size: 15px;
  font-family: inherit;
  transition: border-color 0.2s;
  background: white;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(192, 57, 43, 0.1);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 24px;
  border: none;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.2s;
  gap: 8px;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-primary {
  background: var(--primary);
  color: white;
  width: 100%;
}

.btn-primary:hover:not(:disabled) {
  background: var(--primary-dark);
  transform: translateY(-1px);
}

.btn-secondary {
  background: transparent;
  color: var(--text-light);
  border: 1.5px solid var(--border);
}

.btn-secondary:hover {
  background: var(--bg);
  color: var(--text);
}

.step-actions {
  display: flex;
  gap: 12px;
  margin-top: 24px;
}

.step-actions .btn-primary {
  flex: 1;
}

/* Product cards */
.product-card {
  border: 1.5px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  margin-bottom: 12px;
  cursor: pointer;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  gap: 14px;
}

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

.product-card.selected {
  border-color: var(--primary);
  background: rgba(192, 57, 43, 0.03);
}

.product-checkbox {
  width: 22px;
  height: 22px;
  border: 2px solid var(--border);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: all 0.2s;
}

.product-card.selected .product-checkbox {
  background: var(--primary);
  border-color: var(--primary);
  color: white;
}

.product-info {
  flex: 1;
}

.product-title {
  font-weight: 600;
  font-size: 15px;
}

.product-variant {
  font-size: 13px;
  color: var(--text-light);
}

.product-price {
  font-weight: 600;
  font-size: 14px;
  color: var(--text-light);
}

/* Quantity picker */
.quantity-picker {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 8px;
  font-size: 13px;
  color: var(--text);
}

.quantity-picker label {
  font-weight: 500;
  color: var(--text-light);
}

.qty-btn {
  width: 28px;
  height: 28px;
  border: 1.5px solid var(--border);
  border-radius: 6px;
  background: white;
  cursor: pointer;
  font-size: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
  transition: all 0.15s;
  padding: 0;
  line-height: 1;
}

.qty-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.qty-value {
  min-width: 24px;
  text-align: center;
  font-weight: 600;
  font-size: 15px;
}

.qty-of {
  color: var(--text-light);
}

/* Question cards */
.question-card {
  border: 1.5px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  margin-bottom: 16px;
}

.question-card h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 14px;
}

/* Cost summary */
.cost-summary {
  background: var(--bg);
  border-radius: 10px;
  padding: 20px;
  margin: 20px 0;
}

.cost-line {
  display: flex;
  justify-content: space-between;
  padding: 6px 0;
  font-size: 14px;
}

.cost-line.total {
  border-top: 1.5px solid var(--border);
  margin-top: 8px;
  padding-top: 12px;
  font-weight: 700;
  font-size: 16px;
}

/* Accept cost checkbox */
.accept-cost {
  margin: 16px 0;
}

.accept-cost label {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  cursor: pointer;
  font-size: 14px;
}

.accept-cost input[type="checkbox"] {
  margin-top: 3px;
  width: 18px;
  height: 18px;
  accent-color: var(--primary);
}

/* Condition warning box */
.condition-warning {
  margin-top: 12px;
}

.warning-box {
  background: #fff8e1;
  border: 1.5px solid #ffe082;
  border-radius: 8px;
  padding: 12px 16px;
  font-size: 14px;
  color: #6d4c00;
  margin-bottom: 10px;
  transition: border-color 0.2s;
}

.warning-accept-label {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  cursor: pointer;
  font-size: 13px;
  color: var(--text);
}

.warning-accept-label input[type="checkbox"] {
  margin-top: 3px;
  width: 18px;
  height: 18px;
  accent-color: var(--primary);
}

/* Packing reminder */
.packing-reminder {
  background: var(--bg);
  border-radius: 10px;
  padding: 20px;
  margin-bottom: 20px;
}

.packing-reminder p {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 12px;
}

.packing-reminder ul {
  list-style: none;
  padding: 0;
}

.packing-reminder li {
  position: relative;
  padding-left: 24px;
  margin-bottom: 8px;
  font-size: 14px;
  color: var(--text);
}

.packing-reminder li::before {
  content: '\2713';
  position: absolute;
  left: 0;
  color: var(--primary);
  font-weight: 700;
}

.accept-packing {
  margin: 16px 0;
}

.accept-packing label {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  cursor: pointer;
  font-size: 14px;
}

.accept-packing input[type="checkbox"] {
  margin-top: 3px;
  width: 18px;
  height: 18px;
  accent-color: var(--primary);
}

/* Error messages */
.error-message {
  background: #fdf2f2;
  border: 1px solid #f5c6cb;
  color: var(--error);
  padding: 12px 16px;
  border-radius: 8px;
  font-size: 14px;
  margin-top: 16px;
}

.error-message.hidden {
  display: none;
}

/* Confirmation */
.confirmation-box {
  text-align: center;
  padding: 20px 0;
}

.confirmation-box p {
  margin-bottom: 12px;
  font-size: 14px;
  color: var(--text-light);
}

.confirmation-box .return-id {
  font-family: monospace;
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  background: var(--bg);
  padding: 12px 20px;
  border-radius: 8px;
  display: inline-block;
  margin: 8px 0 20px;
}

.qr-container {
  margin: 24px 0;
}

.qr-container img {
  max-width: 200px;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.qr-container p {
  margin-top: 8px;
  font-size: 13px;
}

.tracking-info {
  background: var(--bg);
  border-radius: 10px;
  padding: 16px;
  margin-top: 16px;
  font-size: 14px;
}

.tracking-info strong {
  display: block;
  margin-bottom: 4px;
}

/* Summary items */
.summary-item {
  border-bottom: 1px solid var(--border);
  padding: 14px 0;
}

.summary-item:last-child {
  border-bottom: none;
}

.summary-item-title {
  font-weight: 600;
  margin-bottom: 4px;
}

.summary-item-detail {
  font-size: 13px;
  color: var(--text-light);
}

/* Loading */
.hidden {
  display: none !important;
}

.btn-loading {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.btn-loading::before {
  content: '';
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Footer */
footer {
  text-align: center;
  padding: 32px 0 20px;
  margin-top: auto;
  font-size: 13px;
  color: var(--text-light);
}

footer a {
  color: var(--primary);
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

footer p + p {
  margin-top: 4px;
}

/* Responsive */
@media (max-width: 480px) {
  .container {
    padding: 12px;
  }

  .step {
    padding: 20px;
  }

  .step-desc {
    padding-left: 0;
  }

  .step-actions {
    flex-direction: column-reverse;
  }
}