:root {
    /* Color Palette */
    --primary-color: #4263eb;
    --primary-hover: #3b5bdb;
    --secondary-color: #f8f9fa;
    --success-color: #40c057;
    --warning-color: #fd7e14;
    --danger-color: #fa5252;
    
    /* Text Colors */
    --text-primary: #212529;
    --text-secondary: #6c757d;
    --text-muted: #adb5bd;
    
    /* Background Colors */
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #e9ecef;
    
    /* Element Colors */
    --address-color: #4263eb;
    --transaction-color: #40c057;
    --selected-color: #fd7e14;
    
    /* Border Colors */
    --border-color: #dee2e6;
    --border-color-dark: #ced4da;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.05), 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.05), 0 4px 6px rgba(0, 0, 0, 0.05);
    
    /* Sizing & Spacing */
    --border-radius: 8px;
    --header-height: 64px;
    --footer-height: 60px;
    --sidebar-width: 400px;
    --transition-speed: 200ms;
  }
  
  /* Dark Mode Support */
  @media (prefers-color-scheme: dark) {
    :root {
      --primary-color: #5c7cfa;
      --primary-hover: #748ffc;
      --secondary-color: #343a40;
      
      --text-primary: #f8f9fa;
      --text-secondary: #ced4da;
      --text-muted: #adb5bd;
      
      --bg-primary: #212529;
      --bg-secondary: #343a40;
      --bg-tertiary: #495057;
      
      --border-color: #495057;
      --border-color-dark: #6c757d;
      
      --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.2);
      --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.2), 0 1px 3px rgba(0, 0, 0, 0.3);
      --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.2), 0 4px 6px rgba(0, 0, 0, 0.2);
    }
  }
  
  /* Reset & Base Styles */
  * {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
  }
  
  html, body {
    height: 100%;
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.5;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
  }
  
  a {
    color: var(--primary-color);
    text-decoration: none;
  }
  
  a:hover {
    text-decoration: underline;
  }
  
  /* Typography */
  h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 0.5rem;
  }
  
  h1 {
    font-size: 1.75rem;
  }
  
  h2 {
    font-size: 1.5rem;
  }
  
  h3 {
    font-size: 1.25rem;
  }
  
  /* Layout */
  .app-container {
    display: grid;
    grid-template-rows: auto 1fr auto;
    min-height: 100vh;
    max-width: 1800px;
    margin: 0 auto;
  }
  
  .main-content {
    display: grid;
    grid-template-columns: 1fr;
    grid-template-rows: auto 1fr auto;
    gap: 1rem;
    padding: 1rem;
    position: relative;
    overflow: hidden;
  }

  .detail-panels {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    height: 100%; /* Ensure container takes full height */
}

  @media (min-width: 992px) {
    .main-content {
      grid-template-columns: 400px 1fr;
      grid-template-rows: 1fr auto;
    }
    .search-panel {
      grid-column: 1;
      grid-row: 1;
    }
    .visualization-panel {
      grid-column: 2;
      grid-row: 1 / span 2;
    }
    .detail-panels {
      grid-column: 1;
      grid-row: 2;
    }
    
  }
  
  /* Header */
  .app-header {
    background-color: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: 0 1rem;
    box-shadow: var(--shadow-sm);
    z-index: 10;
  }
  
  .header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--header-height);
    max-width: 1600px;
    margin: 0 auto;
  }
  
  .logo-container h1 {
    margin: 0;
    font-size: 1.25rem;
    color: var(--primary-color);
  }
  
  /* Breadcrumbs */
  .breadcrumbs {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    flex-wrap: wrap;
  }
  
  .breadcrumb-item {
    display: flex;
    align-items: center;
  }
  
  .breadcrumb-item:not(:last-child)::after {
    content: '/';
    margin: 0 0.5rem;
    color: var(--text-muted);
  }
  
  .breadcrumb-item a {
    color: var(--text-secondary);
    text-decoration: none;
  }
  
  .breadcrumb-item:last-child a,
  .breadcrumb-item a:hover {
    color: var(--primary-color);
  }
  
  /* Search Panel */
  .search-panel {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 1.25rem;
    box-shadow: var(--shadow-md);
    display: flex;
    flex-direction: column;
    gap: 1rem;
    max-height: fit-content;
  }
  
  .search-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
  }
  
  .form-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
  }
  
  .form-control {
    padding: 0.625rem;
    font-size: 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    width: 100%;
    transition: border-color var(--transition-speed) ease-in-out;
  }
  
  .form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(66, 99, 235, 0.25);
  }
  
  .form-control.is-invalid {
    border-color: var(--danger-color);
    box-shadow: 0 0 0 2px rgba(250, 82, 82, 0.25);
  }
  
  .input-with-button {
    display: flex;
    align-items: center;
  }
  
  .input-with-button .form-control {
    border-top-right-radius: 0;
    border-bottom-right-radius: 0;
    flex: 1;
  }
  
  .input-with-button .btn {
    border-top-left-radius: 0;
    border-bottom-left-radius: 0;
  }
  
  .address-group {
    flex: 1;
  }
  
  /* Buttons */
  .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.625rem 1rem;
    font-size: 1rem;
    font-weight: 500;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all var(--transition-speed) ease-in-out;
    border: none;
    background-color: transparent;
    color: var(--text-primary);
  }
  
  .btn-primary {
    background-color: var(--primary-color);
    color: white;
  }
  
  .btn-primary:hover {
    background-color: var(--primary-hover);
  }
  
  .btn-outline {
    border: 1px solid var(--border-color-dark);
    background-color: var(--bg-primary);
  }
  
  .btn-outline:hover {
    background-color: var(--bg-secondary);
  }
  
  .btn-sm {
    padding: 0.4rem 0.75rem;
    font-size: 0.875rem;
  }
  
  .btn-icon {
    padding: 0.625rem;
    height: 42px;
    width: 42px;
  }
  
  .btn-close {
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0.25rem;
    color: var(--text-secondary);
  }
  
  .btn-close:hover {
    color: var(--danger-color);
  }
  
  /* Checkbox */
  .checkbox-group {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 0.5rem;
  }
  
  .form-checkbox {
    width: 16px;
    height: 16px;
    cursor: pointer;
  }
  
  /* Visualization Controls */
  .visualization-controls {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 1rem;
    padding-top: 0.5rem;
    border-top: 1px solid var(--border-color);
  }
  
  .history-select {
    margin-top: 0.5rem;
  }
  
  .view-actions {
    display: flex;
    gap: 0.5rem;
    margin-left: auto;
  }
  
  /* Graph Container */
  .visualization-panel {
    position: relative;
    display: flex;
    flex-direction: column;
    min-height: 400px;
  }
  
  .graph-container {
    position: relative;
    flex: 1;
    border-radius: var(--border-radius);
    background-color: var(--bg-primary);
    box-shadow: var(--shadow-md);
    overflow: hidden;
  }
  
  .graph-container canvas {
    display: block;
    width: 100%;
    height: 100%;
  }
  
  .graph-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1;
  }
  
  .graph-overlay > * {
    pointer-events: auto;
  }
  
  /* Node Count Display */
  .node-count {
    position: absolute;
    top: 1rem;
    left: 1rem;
    background-color: rgba(255, 255, 255, 0.9);
    color: var(--text-secondary);
    padding: 0.25rem 0.5rem;
    border-radius: var(--border-radius);
    font-size: 0.875rem;
    box-shadow: var(--shadow-sm);
  }
  
  @media (prefers-color-scheme: dark) {
    .node-count {
      background-color: rgba(33, 37, 41, 0.9);
      color: var(--text-secondary);
    }
  }
  
  /* Legend */
  .legend {
    position: absolute;
    bottom: 1rem;
    left: 1rem;
    background-color: rgba(255, 255, 255, 0.9);
    padding: 0.5rem;
    border-radius: var(--border-radius);
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
    font-size: 0.875rem;
    box-shadow: var(--shadow-sm);
  }
  
  @media (prefers-color-scheme: dark) {
    .legend {
      background-color: rgba(33, 37, 41, 0.9);
    }
  }
  
  .legend-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
  }
  
  .color-indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
  }
  
  .address-color {
    background-color: var(--address-color);
  }
  
  .transaction-color {
    background-color: var(--transaction-color);
  }
  
  .selected-color {
    background-color: var(--selected-color);
  }
  
  /* Zoom Controls */
  .zoom-controls {
    position: absolute;
    bottom: 1rem;
    right: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
  }
  
  /* Loading Indicator */
  .loading {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(255, 255, 255, 0.8);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    z-index: 10;
  }
  
  @media (prefers-color-scheme: dark) {
    .loading {
      background-color: rgba(33, 37, 41, 0.8);
    }
  }
  
  .spinner {
    width: 40px;
    height: 40px;
    border: 4px solid rgba(66, 99, 235, 0.3);
    border-radius: 50%;
    border-top-color: var(--primary-color);
    animation: spin 1s ease-in-out infinite;
  }
  
  @keyframes spin {
    to { transform: rotate(360deg); }
  }
  
  /* Tooltip */
  .tooltip {
    position: absolute;
    max-width: 200px;
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    padding: 0.5rem 0.75rem;
    box-shadow: var(--shadow-md);
    pointer-events: none;
    z-index: 1000;
    font-size: 0.875rem;
    line-height: 1.4;
    border: 1px solid var(--border-color);
  }
  
  /* Detail Panels */
  .panel {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    transition: opacity 0.2s ease-in-out, visibility 0.2s ease-in-out;
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    max-height: 100%;
    overflow-y: auto;
  }
  
  .panel-in-sidebar {
    position: relative;
    max-height: none;
    opacity: 1;
    visibility: visible;
    height: 320px; /* Fixed height */
    overflow-y: auto;
    
}

#node-detail-panel,
#annotation-panel {
    width: 375px;
    box-sizing: border-box;
    
    /* Prevent horizontal scrolling */
    overflow-x: hidden;
}
.panel-in-sidebar .panel-content {
    height: calc(100% - 3rem); /* Subtract header height */
    overflow-y: auto;
}
  
  .empty-state-message {
    color: var(--text-muted);
    text-align: center;
    padding: 1.5rem 0;
  }
  
  .panel-in-sidebar.empty-panel .annotation-form {
    display: none;
  }
  
  .panel-in-sidebar.empty-panel .empty-state-message {
    display: block;
  }
  
  .panel-in-sidebar:not(.empty-panel) .empty-state-message {
    display: none;
  }

  .panel-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem 1rem;
    border-bottom: 1px solid var(--border-color);
  }
  
  .panel-header h2 {
    margin: 0;
    font-size: 1.125rem;
  }
  
  .panel-content {
    padding: 1rem;
  }
  
  .detail-row {
    display: flex;
    margin-bottom: 0.5rem;
  }
  
  .detail-label {
    width: 120px;
    font-weight: 500;
    color: var(--text-secondary);
  }
  
  .detail-value {
    flex: 1;
    word-break: break-all;
  }
  
  .detail-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: 1rem;
  }
  
  /* Footer */
  .app-footer {
    padding: 1rem;
    background-color: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.875rem;
  }
  
  .footer-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
    text-align: center;
  }
  
  /* Modal */
  .modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    z-index: 1100;
  }
  
  .modal-content {
    background-color: var(--bg-primary);
    border-radius: var(--border-radius);
    max-width: 600px;
    width: 100%;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-lg);
  }
  
  .modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
  }
  
  .modal-header h2 {
    margin: 0;
  }
  
  .modal-body {
    padding: 1rem;
    overflow-y: auto;
  }
  
  .shortcuts {
    margin-top: 0.5rem;
    display: grid;
    grid-template-columns: 1fr;
    gap: 0.5rem;
  }
  
  @media (min-width: 576px) {
    .shortcuts {
      grid-template-columns: repeat(2, 1fr);
    }
  }
  
  .shortcut-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
  }
  
  .key {
    padding: 0.25rem 0.5rem;
    background-color: var(--bg-tertiary);
    border-radius: var(--border-radius);
    font-family: monospace;
    font-size: 0.8125rem;
    white-space: nowrap;
  }

  /* Mobile warning */
.mobile-warning {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.85);
  z-index: 2000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
}

.mobile-warning-content {
  background-color: var(--bg-primary);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  text-align: center;
  max-width: 90%;
  box-shadow: var(--shadow-lg);
}

.mobile-warning-content h3 {
  margin-bottom: 1rem;
}

.mobile-warning-content p {
  margin-bottom: 1.5rem;
}
  
  /* Toast Notifications */
  .toast {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    padding: 0.75rem 1rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-md);
    max-width: 350px;
    z-index: 1050;
    transform: translateY(150%);
    transition: transform 0.3s ease-in-out;
  }
  
  .toast.show {
    transform: translateY(0);
  }
  
  /*.error-toast {
    background-color: var(--danger-color);
    color: white;
  }*/
  
  /* Utility Classes */
  .hidden {
    display: none !important;
  }
  
  .simple-view .graph-container {
    background-color: #fbfbfd;
  }
  
  @media (prefers-color-scheme: dark) {
    .simple-view .graph-container {
      background-color: #1e2124;
    }
  }
  
  /* Responsive Adjustments */
  @media (max-width: 991.98px) {
    .search-panel {
      margin-bottom: 1rem;
    }
  }
  
  @media (max-width: 767.98px) {
    .header-content {
      flex-direction: column;
      padding: 0.5rem 0;
      height: auto;
    }
    
    .main-nav {
      width: 100%;
      overflow-x: auto;
      padding: 0.5rem 0;
    }
    
    .search-form {
      flex-direction: column;
    }
    
    .visualization-controls {
      flex-direction: column;
      align-items: stretch;
    }
    
    .view-actions {
      margin-left: 0;
      justify-content: flex-end;
    }
  }