:root {
    --primary: #10b981;
    --primary-dark: #047857;
    --primary-light: #34d399;
    --secondary: #22c55e;
    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;
    --text-light: #6b7280;
    --border-light: #e5e7eb;
    --error: #ef4444;
    --warning: #f59e0b;
    --success: #10b981;
    --info: #3b82f6;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    --min-touch-target: 44px;
  }

  * { 
    box-sizing: border-box; 
    margin: 0;
    padding: 0;
  }
  
  body { 
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans KR", sans-serif; 
    background: var(--gray-50); 
    color: var(--gray-900);
    line-height: 1.6;
  }

  /* Skip to main content for accessibility */
  .skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--primary);
    color: white;
    padding: 8px;
    text-decoration: none;
    z-index: 100;
  }

  .skip-link:focus {
    top: 0;
  }

  .container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
  }

  /* Notification Messages */
  .message {
    padding: 1rem;
    border-radius: 0.5rem;
    margin: 1rem 0;
    display: none;
    animation: slideDown 0.3s ease;
  }

  .message.show {
    display: block;
  }

  .message.error {
    background: #fef2f2;
    border: 1px solid #fecaca;
    color: var(--error);
  }

  .message.success {
    background: #f0fdf4;
    border: 1px solid #86efac;
    color: var(--success);
  }

  .message.info {
    background: #eff6ff;
    border: 1px solid #93c5fd;
    color: var(--info);
  }

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

  /* Loading Skeleton */
  .skeleton {
    background: linear-gradient(90deg, var(--gray-200) 25%, var(--gray-100) 50%, var(--gray-200) 75%);
    background-size: 200% 100%;
    animation: loading 1.5s infinite;
  }

  @keyframes loading {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
  }

  .header { 
    background: white;
    box-shadow: var(--shadow-sm);
    position: sticky;
    top: 0;
    z-index: 100;
  }
  
  .nav { 
    display: flex; 
    justify-content: space-between; 
    align-items: center; 
    padding: 1rem 0;
  }
  
  .nav-left {
    display: flex;
    align-items: center;
    gap: 2rem;
  }

  .logo { 
    font-size: 1.75rem; 
    font-weight: 800; 
    background: linear-gradient(135deg, var(--primary), var(--secondary)); 
    -webkit-background-clip: text; 
    -webkit-text-fill-color: transparent;
    background-clip: text;
  }

  .logo a {
    text-decoration: none;
    color: inherit;
  }

  .breadcrumb {
    display: flex;
    list-style: none;
    padding: 0;
    margin: 0;
    gap: 0.5rem;
    align-items: center;
  }

  .breadcrumb li {
    color: var(--text-light);
    font-size: 0.9rem;
  }

  .breadcrumb li:not(:last-child)::after {
    content: '>';
    margin-left: 0.5rem;
    color: var(--gray-300);
  }

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

  .breadcrumb a:hover {
    text-decoration: underline;
  }

  .user-menu {
    display: flex;
    align-items: center;
    gap: 1rem;
  }

  .user-info {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--gray-100);
    border-radius: 2rem;
    font-size: 0.9rem;
  }

  .user-avatar {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.8rem;
    font-weight: bold;
  }

  .auth-btn {
    padding: 0.5rem 1rem;
    background: var(--primary);
    color: white;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.3s ease;
  }

  .auth-btn:hover {
    background: var(--primary-dark);
  }

  .main {
    padding: 2rem 0;
  }

  .search-layout {
    display: grid;
    grid-template-columns: 400px 1fr;
    gap: 3rem;
    align-items: start;
  }

  .search-panel {
    background: white;
    border-radius: 1.5rem;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border-light);
    position: sticky;
    top: 120px;
    overflow: hidden;
  }

  .panel-header {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    padding: 2rem;
    text-align: center;
  }

  .panel-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
  }

  .panel-subtitle {
    opacity: 0.9;
    font-size: 0.95rem;
  }

  .panel-content {
    padding: 2rem;
  }

  .form-section {
    margin-bottom: 2rem;
  }

  .section-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--gray-900);
    margin-bottom: 1rem;
  }

  .form-group {
    margin-bottom: 1.5rem;
  }

  .form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--gray-900);
    font-size: 0.95rem;
  }

  .form-input, .form-select, .form-textarea {
    width: 100%;
    padding: 0.875rem;
    border: 2px solid var(--gray-200);
    border-radius: 0.75rem;
    font-size: 0.95rem;
    transition: all 0.3s ease;
    min-height: var(--min-touch-target);
  }

  .form-input:focus, .form-select:focus, .form-textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.1);
  }

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

  .quick-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 0.75rem;
  }

  .quick-tag {
    padding: 0.5rem 0.75rem;
    background: var(--gray-100);
    color: var(--gray-700);
    border-radius: 1rem;
    font-size: 0.85rem;
    cursor: pointer;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    min-height: var(--min-touch-target);
    display: inline-flex;
    align-items: center;
    touch-action: manipulation;
  }

  .quick-tag:hover {
    background: var(--primary-light);
    color: white;
  }

  .quick-tag:focus {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
  }

  .quick-tag[aria-checked="true"] {
    background: var(--primary);
    color: white;
    border-color: var(--primary-dark);
  }

  .budget-range {
    margin: 1rem 0;
  }

  .budget-display {
    text-align: center;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 1rem;
  }

  .range-slider {
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: var(--gray-200);
    outline: none;
    -webkit-appearance: none;
  }

  .range-slider::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--primary);
    cursor: pointer;
    box-shadow: var(--shadow-md);
  }

  .range-slider::-moz-range-thumb {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--primary);
    cursor: pointer;
    border: none;
    box-shadow: var(--shadow-md);
  }

  .budget-labels {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    color: var(--text-light);
    margin-top: 0.5rem;
  }

  .search-btn {
    width: 100%;
    padding: 1rem;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    border: none;
    border-radius: 0.75rem;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    min-height: var(--min-touch-target);
  }

  .search-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
  }

  .search-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
  }

  .results-panel {
    background: white;
    border-radius: 1.5rem;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-light);
    min-height: 700px;
    position: relative;
  }

  .welcome-state {
    text-align: center;
    padding: 4rem 2rem;
    color: var(--text-light);
  }

  .welcome-icon {
    font-size: 5rem;
    margin-bottom: 2rem;
    opacity: 0.6;
  }

  .welcome-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 1rem;
  }

  .loading-state {
    display: none;
    text-align: center;
    padding: 4rem 2rem;
  }

  .loading-spinner {
    width: 80px;
    height: 80px;
    border: 4px solid var(--gray-200);
    border-top: 4px solid var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 2rem;
  }

  @keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
  }

  .loading-text {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--gray-700);
    margin-bottom: 0.5rem;
  }

  .progress-bar {
    width: 200px;
    height: 4px;
    background: var(--gray-200);
    border-radius: 2px;
    margin: 1rem auto;
    overflow: hidden;
  }

  .progress-fill {
    height: 100%;
    background: var(--primary);
    border-radius: 2px;
    transition: width 0.3s ease;
  }

  .results-display {
    display: none;
    padding: 2rem;
  }

  .results-header {
    text-align: center;
    margin-bottom: 3rem;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border-light);
  }

  .results-title {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 0.5rem;
  }

  .recommendation-list {
    display: grid;
    gap: 2rem;
  }

  .recommendation-card {
    background: white;
    border: 2px solid var(--border-light);
    border-radius: 1.5rem;
    padding: 2rem;
    transition: all 0.3s ease;
    position: relative;
    cursor: pointer;
  }

  .recommendation-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient);
    border-radius: 1.5rem 1.5rem 0 0;
  }

  .recommendation-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-light);
  }

  .recommendation-card:focus-within {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
  }

  .card-rank {
    position: absolute;
    top: -12px;
    right: 2rem;
    background: var(--gradient);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 1rem;
    font-weight: 700;
    font-size: 0.9rem;
  }

  .product-header {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 2rem;
    margin-bottom: 2rem;
  }

  .product-info h3 {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 0.5rem;
  }

  .product-company {
    color: var(--primary);
    font-weight: 600;
    margin-bottom: 1rem;
  }

  .product-description {
    color: var(--gray-600);
    line-height: 1.6;
  }

  .match-score-container {
    text-align: center;
    min-width: 120px;
  }

  .match-score {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    background: conic-gradient(var(--primary) 0deg, var(--primary-light) var(--score-angle), var(--gray-200) var(--score-angle));
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    margin: 0 auto 1rem;
  }

  .match-score::before {
    content: '';
    width: 80px;
    height: 80px;
    background: white;
    border-radius: 50%;
    position: absolute;
  }

  .score-value {
    font-size: 1.4rem;
    font-weight: 800;
    color: var(--primary);
    position: relative;
    z-index: 1;
  }

  .score-label {
    font-size: 0.9rem;
    color: var(--text-light);
    font-weight: 600;
  }

  .product-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin: 1.5rem 0;
  }

  .product-tag {
    padding: 0.25rem 0.75rem;
    background: var(--gray-100);
    color: var(--gray-700);
    border-radius: 1rem;
    font-size: 0.8rem;
    font-weight: 500;
  }

  .product-tag.match {
    background: var(--primary);
    color: white;
  }

  .product-actions {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-light);
  }

  .action-btn {
    flex: 1;
    padding: 0.5rem;
    background: transparent;
    border: 2px solid var(--gray-300);
    border-radius: 0.5rem;
    color: var(--gray-700);
    font-size: 0.9rem;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
  }

  .action-btn:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: var(--gray-50);
  }

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

  .action-btn.primary:hover {
    background: var(--primary-dark);
    border-color: var(--primary-dark);
  }

  .rank-1 { --gradient: linear-gradient(135deg, #10b981, #34d399); }
  .rank-2 { --gradient: linear-gradient(135deg, #3b82f6, #60a5fa); }
  .rank-3 { --gradient: linear-gradient(135deg, #8b5cf6, #a78bfa); }

  /* Login Modal */
  .modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    align-items: center;
    justify-content: center;
  }

  .modal.show {
    display: flex;
  }

  .modal-content {
    background: white;
    padding: 2rem;
    border-radius: 1rem;
    max-width: 400px;
    width: 90%;
    animation: slideUp 0.3s ease;
  }

  @keyframes slideUp {
    from {
      transform: translateY(50px);
      opacity: 0;
    }
    to {
      transform: translateY(0);
      opacity: 1;
    }
  }

  .modal-header {
    text-align: center;
    margin-bottom: 2rem;
  }

  .modal-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 0.5rem;
  }

  .modal-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: transparent;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--gray-600);
  }

  /* Accessibility improvements */
  .visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
  }

  /* Responsive Design */
  @media (max-width: 1024px) {
    .search-layout {
      grid-template-columns: 1fr;
      gap: 2rem;
    }
    .search-panel {
      position: static;
    }
  }

  @media (max-width: 768px) {
    .container {
      padding: 0 1rem;
    }
    .product-header {
      grid-template-columns: 1fr;
    }
    .match-score-container {
      margin-top: 1rem;
    }
    .nav {
      flex-direction: column;
      gap: 1rem;
    }
  }

  /* Print styles */
  @media print {
    .header, .search-panel {
      display: none;
    }
    .results-panel {
      box-shadow: none;
      border: 1px solid #000;
    }
  }