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

:root {
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-card: #ffffff;
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --border-color: #e2e8f0;
  --accent-color: #3b82f6;
  --accent-hover: #2563eb;
  --success-color: #10b981;
  --success-hover: #059669;
  --danger-color: #ef4444;
  --danger-hover: #dc2626;
  --warning-color: #f59e0b;
  --info-color: #06b6d4;
  --purple-color: #8b5cf6;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-card: #334155;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --border-color: #475569;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.4), 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.4), 0 10px 10px -5px rgba(0, 0, 0, 0.3);
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  transition: all 0.3s ease;
  font-size: 16px;
}

.container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 1rem;
}

.header {
  text-align: center;
  margin-bottom: 2rem;
  padding: 3rem 2rem;
  background: linear-gradient(135deg, var(--bg-card) 0%, var(--bg-secondary) 100%);
  border-radius: 16px;
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}

.header::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent-color), var(--success-color), var(--warning-color));
}

.header h1 {
  color: var(--accent-color);
  margin-bottom: 0.75rem;
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.025em;
}

.header p {
  color: var(--text-secondary);
  font-size: clamp(1rem, 2.5vw, 1.25rem);
  font-weight: 400;
  max-width: 600px;
  margin: 0 auto;
}

.theme-toggle {
  position: fixed;
  top: 1.5rem;
  right: 1.5rem;
  background: var(--accent-color);
  color: white;
  border: none;
  padding: 0.75rem;
  border-radius: 12px;
  cursor: pointer;
  font-size: 1.25rem;
  box-shadow: var(--shadow-lg);
  transition: all 0.3s ease;
  z-index: 1000;
  width: 50px;
  height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  background: var(--accent-hover);
  transform: scale(1.05);
}

.form-section {
  background: var(--bg-card);
  padding: 2rem;
  border-radius: 16px;
  margin-bottom: 2rem;
  box-shadow: var(--shadow);
  border: 1px solid var(--border-color);
  transition: all 0.3s ease;
}

.form-section:hover {
  box-shadow: var(--shadow-lg);
}

.form-section h2 {
  color: var(--accent-color);
  margin-bottom: 1.5rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-size: clamp(1.25rem, 3vw, 1.5rem);
  font-weight: 600;
}

.form-actions {
  display: flex;
  gap: 1rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.form-group {
  display: flex;
  flex-direction: column;
}

.form-group label {
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--text-primary);
  font-size: 0.9rem;
}

.form-group input,
.form-group select,
.form-group textarea {
  padding: 0.875rem 1rem;
  border: 2px solid var(--border-color);
  border-radius: 10px;
  background: var(--bg-primary);
  color: var(--text-primary);
  font-size: 1rem;
  font-family: inherit;
  transition: all 0.3s ease;
  resize: none;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--accent-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
  transform: translateY(-1px);
}

.form-group textarea {
  resize: vertical;
  min-height: 100px;
}

.form-group.full-width {
  grid-column: 1 / -1;
}

.btn {
  padding: 0.875rem 1.5rem;
  border: none;
  border-radius: 10px;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s ease;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  text-decoration: none;
  font-family: inherit;
  min-height: 44px;
}

.btn-primary {
  background: var(--accent-color);
  color: white;
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-success {
  background: var(--success-color);
  color: white;
}

.btn-success:hover {
  background: var(--success-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-danger {
  background: var(--danger-color);
  color: white;
}

.btn-danger:hover {
  background: var(--danger-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 2px solid var(--border-color);
}

.btn-secondary:hover {
  background: var(--border-color);
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  margin: 2rem 0;
  flex-wrap: wrap;
}

.guide-preview {
  background: var(--bg-card);
  padding: 2rem;
  border-radius: 16px;
  box-shadow: var(--shadow);
  margin-bottom: 2rem;
  border: 1px solid var(--border-color);
}

.guide-item {
  border-radius: 16px;
  padding: 2rem;
  margin-bottom: 2rem;
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
  page-break-inside: avoid;
  font-size: 0.9rem;
  position: relative;
  overflow: hidden;
}

.guide-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 6px;
  background: linear-gradient(90deg, var(--accent-color), var(--success-color), var(--info-color), var(--purple-color));
}

.guide-header {
  text-align: center;
  margin-bottom: 2rem;
  padding: 1.5rem;
  background: linear-gradient(135deg, var(--accent-color), var(--info-color));
  border-radius: 12px;
  color: #222;
  position: relative;
}

.guide-header::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 0;
  border-left: 10px solid transparent;
  border-right: 10px solid transparent;
  border-top: 10px solid var(--info-color);
}

.guide-header h3 {
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.guide-header p {
  font-size: 1rem;
  opacity: 0.9;
  margin: 0.25rem 0;
}

.guide-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin: 2rem 0;

}

.sender-info,
.recipient-info {
  padding: 1.5rem;
  background: #0f172a;
  border-radius: 12px;
  border: 2px solid;
  position: relative;
}

.sender-info {
  border-color: var(--success-color);
}

.recipient-info {
  border-color: var(--warning-color);
}

.sender-info::before {
  content: '📤';
  position: absolute;
  top: -15px;
  left: 15px;
  background: #0f172a;
  padding: 5px 10px;
  border-radius: 20px;
  font-size: 1.2rem;
  border: 2px solid var(--success-color);
}

.recipient-info::before {
  content: '📥';
  position: absolute;
  top: -15px;
  left: 15px;
  background: #0f172a;
  padding: 5px 10px;
  border-radius: 20px;
  font-size: 1.2rem;
  border: 2px solid var(--warning-color);
}

.info-title {
  font-weight: 700;
  margin-bottom: 1rem;
  font-size: 1.1rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.5rem 0;
  border-bottom: 2px solid;
}

.sender-info .info-title {
  color: var(--success-color);
  border-color: var(--success-color);
}

.recipient-info .info-title {
  color: var(--warning-color);
  border-color: var(--warning-color);
}

.info-item {
  color: #fff;
  font-weight: 500;
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
  line-height: 1.4;
  padding: 0.25rem 0;
}

.info-item strong {
  color: #94a3b8;
  font-weight: 700;
}

.guide-footer {
  margin-top: 2rem;
  padding: 1.5rem;
  background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--border-color) 100%);
  border-radius: 12px;
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
}

.barcode-section {
  margin: 1.5rem 0;
  text-align: center;
  padding: 1rem;
  background: #0f172a;
  border-radius: 8px;
  border: 2px dashed var(--accent-color);
}

.barcode-placeholder {
  height: 40px;
  background: repeating-linear-gradient(90deg,
      #fff 0px,
      #000 2px,
      transparent 2px,
      transparent 4px);
  margin: 0.5rem 0;
  border-radius: 4px;
}

.counter {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin: 1rem 0;
  flex-wrap: wrap;
}

.counter button {
  width: 44px;
  height: 44px;
  border: none;
  border-radius: 10px;
  background: var(--accent-color);
  color: white;
  font-size: 1.2rem;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
}

.counter button:hover {
  background: var(--accent-hover);
  transform: scale(1.05);
}

.counter span {
  font-size: 1.2rem;
  font-weight: 600;
  min-width: 120px;
  text-align: center;
  padding: 0.5rem 1rem;
  background: var(--bg-secondary);
  border-radius: 10px;
  border: 1px solid var(--border-color);
}

.alert {
  padding: 1rem 1.5rem;
  border-radius: 10px;
  margin-bottom: 1rem;
  font-weight: 500;
}

.alert-success {
  background: rgba(16, 185, 129, 0.1);
  color: var(--success-color);
  border: 1px solid rgba(16, 185, 129, 0.2);
}

.alert-danger {
  background: rgba(239, 68, 68, 0.1);
  color: var(--danger-color);
  border: 1px solid rgba(239, 68, 68, 0.2);
}

/* Responsive Design */
@media (max-width: 1200px) {
  .container {
    max-width: 100%;
    padding: 1rem;
  }
}

@media (max-width: 768px) {
  .container {
    padding: 0.75rem;
  }

  .header {
    padding: 2rem 1rem;
    margin-bottom: 1.5rem;
  }

  .form-section {
    padding: 1.5rem;
    margin-bottom: 1.5rem;
  }

  .form-grid {
    grid-template-columns: 1fr;
    gap: 1rem;
  }

  .guide-content {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .actions {
    flex-direction: column;
    align-items: stretch;
  }

  .form-actions {
    flex-direction: column;
  }

  .counter {
    justify-content: center;
  }

  .theme-toggle {
    top: 1rem;
    right: 1rem;
    width: 44px;
    height: 44px;
  }
}

@media (max-width: 480px) {
  .header {
    padding: 1.5rem 0.75rem;
  }

  .form-section {
    padding: 1rem;
  }

  .guide-item {
    padding: 1.5rem;
  }

  .sender-info,
  .recipient-info {
    padding: 1rem;
  }
}

/* Print Styles */
@media print {
  @page {
    margin: 0.5in;
    size: letter;
  }

  * {
    -webkit-print-color-adjust: exact !important;
    color-adjust: exact !important;
    print-color-adjust: exact !important;
  }

  body {
    background: white !important;
    color: black !important;
    font-size: 11pt;
    line-height: 1.3;
  }

  .header,
  .form-section,
  .actions,
  .theme-toggle,
  .alert {
    display: none !important;
  }

  .guide-preview {
    box-shadow: none !important;
    margin: 0 !important;
    padding: 0 !important;
    background: white !important;
    border: none !important;
  }

  .guide-preview h2 {
    display: none !important;
  }

  .info-item {
    color: #fff !important;
    font-weight: 500 !important;
  }

  .info-item strong {
    color: #b8b8b8 !important;
    font-weight: 700 !important;
  }

  .guide-item {
    break-inside: avoid;
    margin-bottom: 0.5in !important;
    background: linear-gradient(135deg, #ffffff 0%, #f8fafc 100%) !important;
    box-shadow: none !important;
    page-break-inside: avoid;
    padding: 1.5rem !important;
  }

  .guide-item::before {
    background: linear-gradient(90deg, #3b82f6, #10b981, #06b6d4, #8b5cf6) !important;
  }

  .guide-header {
    background: linear-gradient(135deg, #3b82f6, #06b6d4) !important;
    color: white !important;
    -webkit-print-color-adjust: exact !important;
  }

  .guide-header h3 {
    color: white !important;
    font-size: 16pt !important;
  }

  .guide-header p {
    color: white !important;
  }

  .info-title {
    font-size: 12pt !important;
  }

  .sender-info .info-title {
    color: #10b981 !important;
    border-color: #10b981 !important;
  }

  .recipient-info .info-title {
    color: #f59e0b !important;
    border-color: #f59e0b !important;
  }

  .sender-info {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%) !important;
    border-color: #10b981 !important;
  }

  .recipient-info {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%) !important;
    border-color: #f59e0b !important;
  }

  .sender-info::before,
  .recipient-info::before {
    background: #0f172a !important;
  }

  .guide-content {
    grid-template-columns: 1fr 1fr;
  }

  .guide-footer {
    background: linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%) !important;
    border-color: #e2e8f0 !important;
  }

  .barcode-section {
    background: white !important;
    border-color: #3b82f6 !important;
  }

  .barcode-placeholder {
    background: repeating-linear-gradient(90deg,
        #000 0px,
        #000 2px,
        transparent 2px,
        transparent 4px) !important;
  }
}

.loading {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid rgba(255, 255, 255, .3);
  border-radius: 50%;
  border-top-color: #fff;
  animation: spin 1s ease-in-out infinite;
}

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

.fade-in {
  animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}