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

    :root {
      --background: #ffffff;
      --foreground: #0f172a;
      --card: #f8fafc;
      --card-hover: #f1f5f9;
      --border: #e2e8f0;
      --muted: #64748b;
      --accent: #2563eb;
      --accent-hover: #1d4ed8;
    }

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

    /* Header */
    .header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255, 255, 255, 0.9);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border);
    }

    .header-content {
      max-width: 1400px;
      margin: 0 auto;
      padding: 1rem 1.5rem;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 1.5rem;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 0.5rem;
      font-weight: 700;
      font-size: 1.25rem;
      color: var(--foreground);
      text-decoration: none;
    }

    .logo svg {
      width: 28px;
      height: 28px;
    }

    .search-container {
      flex: 1;
      max-width: 480px;
    }

    .search-box {
      position: relative;
      width: 100%;
    }

    .search-input {
      width: 100%;
      padding: 0.625rem 1rem 0.625rem 2.75rem;
      background: var(--card);
      border: 1px solid var(--border);
      border-radius: 8px;
      color: var(--foreground);
      font-size: 0.875rem;
      outline: none;
      transition: border-color 0.2s, box-shadow 0.2s;
    }

    .search-input::placeholder {
      color: var(--muted);
    }

    .search-input:focus {
      border-color: var(--accent);
      box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
    }

    .search-icon {
      position: absolute;
      left: 0.875rem;
      top: 50%;
      transform: translateY(-50%);
      color: var(--muted);
      pointer-events: none;
    }

    .header-actions {
      display: flex;
      align-items: center;
      gap: 0.75rem;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
      padding: 0.5rem 1rem;
      border-radius: 8px;
      font-size: 0.875rem;
      font-weight: 500;
      cursor: pointer;
      transition: all 0.2s;
      text-decoration: none;
      border: none;
    }

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

    .btn-primary:hover {
      opacity: 0.9;
    }

    .btn-ghost {
      background: transparent;
      color: var(--muted);
      border: 1px solid transparent;
    }

    .btn-ghost:hover {
      color: var(--foreground);
      background: var(--card);
    }

    /* Hero Section */
    .hero {
      text-align: center;
      padding: 4rem 1.5rem 3rem;
      max-width: 800px;
      margin: 0 auto;
    }

    .hero h1 {
      font-size: clamp(2rem, 5vw, 3.5rem);
      font-weight: 700;
      letter-spacing: -0.02em;
      margin-bottom: 1rem;
      text-wrap: balance;
    }

    .hero p {
      font-size: 1.125rem;
      color: var(--muted);
      max-width: 600px;
      margin: 0 auto;
      text-wrap: pretty;
    }

    /* Main Layout */
    .main-layout {
      display: flex;
      max-width: 1400px;
      margin: 0 auto;
      padding: 0 1.5rem 4rem;
      gap: 2rem;
    }

    /* Sidebar */
    .sidebar {
      width: 240px;
      flex-shrink: 0;
      position: sticky;
      top: 80px;
      height: fit-content;
      max-height: calc(100vh - 100px);
      overflow-y: auto;
    }

    .sidebar-title {
      font-size: 0.75rem;
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 0.05em;
      color: var(--muted);
      margin-bottom: 0.75rem;
      padding: 0 0.75rem;
    }

    .category-list {
      list-style: none;
    }

    .category-item {
      margin-bottom: 0.125rem;
    }

    .category-btn {
      width: 100%;
      display: flex;
      align-items: center;
      gap: 0.625rem;
      padding: 0.625rem 0.75rem;
      background: transparent;
      border: none;
      border-radius: 6px;
      color: var(--muted);
      font-size: 0.875rem;
      cursor: pointer;
      transition: all 0.15s;
      text-align: left;
    }

    .category-btn:hover {
      background: var(--card);
      color: var(--foreground);
    }

    .category-btn.active {
      background: var(--card);
      color: var(--foreground);
      font-weight: 500;
    }

    .category-icon {
      width: 18px;
      height: 18px;
      opacity: 0.7;
    }

    .category-count {
      margin-left: auto;
      font-size: 0.75rem;
      color: var(--muted);
      background: var(--border);
      padding: 0.125rem 0.5rem;
      border-radius: 999px;
    }

    /* Content Area */
    .content {
      flex: 1;
      min-width: 0;
    }

    .content-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 1.5rem;
      flex-wrap: wrap;
      gap: 1rem;
    }

    .results-count {
      font-size: 0.875rem;
      color: var(--muted);
    }

    .results-count span {
      color: var(--foreground);
      font-weight: 600;
    }

    .view-toggle {
      display: flex;
      background: var(--card);
      border-radius: 8px;
      padding: 0.25rem;
      border: 1px solid var(--border);
    }

    .view-btn {
      padding: 0.375rem 0.75rem;
      background: transparent;
      border: none;
      border-radius: 6px;
      color: var(--muted);
      cursor: pointer;
      transition: all 0.15s;
    }

    .view-btn.active {
      background: var(--border);
      color: var(--foreground);
    }

    .view-btn:hover:not(.active) {
      color: var(--foreground);
    }

    /* Cards Grid */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
      gap: 1rem;
    }

    .tool-card {
      background: var(--card);
      border: 1px solid var(--border);
      border-radius: 12px;
      padding: 1.25rem;
      transition: all 0.2s;
      cursor: pointer;
    }

    .tool-card:hover {
      background: var(--card-hover);
      border-color: #cbd5e1;
      transform: translateY(-2px);
    }

    .card-header {
      display: flex;
      align-items: flex-start;
      justify-content: space-between;
      margin-bottom: 0.75rem;
    }

    .card-category {
      display: inline-flex;
      align-items: center;
      gap: 0.375rem;
      font-size: 0.75rem;
      color: var(--accent);
      background: rgba(59, 130, 246, 0.1);
      padding: 0.25rem 0.625rem;
      border-radius: 999px;
    }

    .card-badge {
      font-size: 0.625rem;
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 0.05em;
      padding: 0.25rem 0.5rem;
      border-radius: 4px;
      background: rgba(34, 197, 94, 0.1);
      color: #22c55e;
    }

    .card-title {
      font-size: 1rem;
      font-weight: 600;
      margin-bottom: 0.5rem;
      color: var(--foreground);
    }

    .card-tools {
      display: flex;
      flex-wrap: wrap;
      gap: 0.375rem;
      margin-bottom: 0.75rem;
    }

    .tool-tag {
      font-size: 0.75rem;
      padding: 0.25rem 0.625rem;
      background: var(--border);
      border-radius: 6px;
      color: var(--muted);
      transition: all 0.15s;
    }

    .tool-tag:hover {
      background: #cbd5e1;
      color: var(--foreground);
    }

    .card-description {
      font-size: 0.875rem;
      color: var(--muted);
      line-height: 1.5;
      margin-bottom: 1rem;
    }

    .card-footer {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding-top: 0.75rem;
      border-top: 1px solid var(--border);
    }

    .card-link {
      display: inline-flex;
      align-items: center;
      gap: 0.375rem;
      font-size: 0.8125rem;
      color: var(--accent);
      text-decoration: none;
      font-weight: 500;
      transition: gap 0.2s;
    }

    .card-link:hover {
      gap: 0.5rem;
    }

    /* List View */
    .cards-list {
      display: flex;
      flex-direction: column;
      gap: 0.75rem;
    }

    .cards-list .tool-card {
      display: flex;
      align-items: center;
      gap: 1.25rem;
      padding: 1rem 1.25rem;
    }

    .cards-list .card-header {
      margin-bottom: 0;
      flex-direction: column;
      align-items: flex-start;
      gap: 0.25rem;
      min-width: 120px;
    }

    .cards-list .card-content {
      flex: 1;
      display: flex;
      flex-direction: column;
      gap: 0.375rem;
    }

    .cards-list .card-title {
      margin-bottom: 0;
    }

    .cards-list .card-tools {
      margin-bottom: 0;
    }

    .cards-list .card-description {
      margin-bottom: 0;
      display: -webkit-box;
      -webkit-line-clamp: 1;
      -webkit-box-orient: vertical;
      overflow: hidden;
    }

    .cards-list .card-footer {
      border-top: none;
      padding-top: 0;
      flex-shrink: 0;
    }

    /* Empty State */
    .empty-state {
      text-align: center;
      padding: 4rem 2rem;
      color: var(--muted);
    }

    .empty-state svg {
      width: 64px;
      height: 64px;
      margin-bottom: 1rem;
      opacity: 0.5;
    }

    .empty-state h3 {
      font-size: 1.125rem;
      color: var(--foreground);
      margin-bottom: 0.5rem;
    }

    /* Mobile Sidebar Toggle */
    .mobile-filter-btn {
      display: none;
      align-items: center;
      gap: 0.5rem;
      padding: 0.625rem 1rem;
      background: var(--card);
      border: 1px solid var(--border);
      border-radius: 8px;
      color: var(--foreground);
      font-size: 0.875rem;
      cursor: pointer;
    }

    .sidebar-overlay {
      display: none;
      position: fixed;
      inset: 0;
      background: rgba(0, 0, 0, 0.5);
      z-index: 40;
    }

    /* Responsive */
    @media (max-width: 1024px) {
      .sidebar {
        width: 220px;
      }
    }

    @media (max-width: 768px) {
      .header-content {
        flex-wrap: wrap;
      }

      .search-container {
        order: 3;
        max-width: 100%;
        width: 100%;
      }

      .mobile-filter-btn {
        display: flex;
      }

      .sidebar {
        position: fixed;
        left: 0;
        top: 0;
        bottom: 0;
        width: 280px;
        background: var(--background);
        z-index: 50;
        padding: 1.5rem;
        transform: translateX(-100%);
        transition: transform 0.3s;
        max-height: 100vh;
      }

      .sidebar.open {
        transform: translateX(0);
      }

      .sidebar-overlay.open {
        display: block;
      }

      .main-layout {
        flex-direction: column;
      }

      .cards-grid {
        grid-template-columns: 1fr;
      }

      .cards-list .tool-card {
        flex-direction: column;
        align-items: flex-start;
      }

      .cards-list .card-footer {
        width: 100%;
        margin-top: 0.75rem;
        padding-top: 0.75rem;
        border-top: 1px solid var(--border);
      }
    }

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

    .tool-card {
      animation: fadeIn 0.3s ease-out;
    }

    /* Scrollbar */
    ::-webkit-scrollbar {
      width: 8px;
      height: 8px;
    }

    ::-webkit-scrollbar-track {
      background: var(--background);
    }

    ::-webkit-scrollbar-thumb {
      background: var(--border);
      border-radius: 4px;
    }

    ::-webkit-scrollbar-thumb:hover {
      background: #cbd5e1;
    }