/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  }
  
  body {
    background-color: #f4f4f9;
    color: #333;
    line-height: 1.6;
  }
  
  /* Header Styles */
  header {
    background-color: #1a73e8;
    color: white;
    padding: 1rem;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
  }
  
  header h1 {
    text-align: center;
    margin-bottom: 1rem;
  }
  
  nav ul {
    display: flex;
    justify-content: center;
    list-style: none;
    gap: 1rem;
    padding: 0.5rem 0;
  }
  
  nav a {
    color: white;
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    transition: background-color 0.3s;
  }
  
  nav a:hover, nav a.active {
    background-color: rgba(255, 255, 255, 0.2);
  }
  
  /* Main Content Styles */
  main {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1rem;
  }
  
  .card {
    background-color: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    padding: 1.5rem;
    margin-bottom: 2rem;
  }
  
  .section-content {
    display: none;
  }
  
  .section-content.active {
    display: block;
  }
  
  h2 {
    color: #1a73e8;
    margin-bottom: 1.5rem;
    border-bottom: 1px solid #eee;
    padding-bottom: 0.5rem;
  }
  
  h3 {
    color: #444;
    margin: 1.5rem 0 1rem;
  }
  
  h4 {
    color: #555;
    margin: 1rem 0 0.5rem;
  }
  
  /* Form Styles */
  form {
    background-color: #f8f9fa;
    padding: 1.5rem;
    border-radius: 6px;
    margin-bottom: 1.5rem;
  }
  
  .form-group {
    margin-bottom: 1rem;
  }
  
  label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
  }
  
  input, textarea, select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 1rem;
  }
  
  input:focus, textarea:focus, select:focus {
    outline: none;
    border-color: #1a73e8;
    box-shadow: 0 0 0 2px rgba(26, 115, 232, 0.2);
  }
  
  .checkbox-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
  }
  
  .checkbox-group input {
    width: auto;
  }
  
  /* Button Styles */
  .btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    transition: background-color 0.2s, transform 0.1s;
  }
  
  .btn:hover {
    transform: translateY(-1px);
  }
  
  .primary-btn {
    background-color: #1a73e8;
    color: white;
  }
  
  .primary-btn:hover {
    background-color: #1557b0;
  }
  
  .secondary-btn {
    background-color: #f1f3f4;
    color: #1a73e8;
  }
  
  .secondary-btn:hover {
    background-color: #e8eaed;
  }
  
  .danger-btn {
    background-color: #ea4335;
    color: white;
  }
  
  .danger-btn:hover {
    background-color: #d33426;
  }
  
  /* Table Styles */
  .table-container {
    overflow-x: auto;
    margin-top: 1.5rem;
  }
  
  .filter-controls {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
    padding: 0.5rem;
    background-color: #f8f9fa;
    border-radius: 4px;
  }
  
  .filter-controls label {
    margin-bottom: 0;
    white-space: nowrap;
  }
  
  .filter-controls select {
    width: auto;
  }
  
  table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 0.5rem;
  }
  
  th, td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid #eee;
  }
  
  th {
    background-color: #f8f9fa;
    font-weight: 600;
  }
  
  tr:hover {
    background-color: #f8f9fa;
  }
  
  /* Import/Export Section */
  .import-export-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }
  
  .export-card, .import-card {
    background-color: #f8f9fa;
    padding: 1.5rem;
    border-radius: 6px;
  }
  
  .export-options, .import-options {
    margin-top: 1.5rem;
  }
  
  .export-options button {
    margin-right: 0.5rem;
    margin-bottom: 0.5rem;
  }
  
  .import-control {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
    flex-wrap: wrap;
  }
  
  input[type="file"] {
    padding: 0.5rem;
    flex: 1;
  }
  
  /* Footer Styles */
  footer {
    text-align: center;
    padding: 1.5rem;
    margin-top: 2rem;
    background-color: #f8f9fa;
    color: #70757a;
  }
  
  /* Responsive Adjustments */
  @media (max-width: 768px) {
    nav ul {
      flex-wrap: wrap;
    }
    .import-export-container {
      grid-template-columns: 1fr;
    }
    th, td {
      padding: 0.5rem;
    }
  }