html, body {
    height: 100%;
    margin: 0;
    font-family: 'Montserrat', sans-serif;
    background-color: #ffffff;
    color: #555;
    display: flex;
    flex-direction: column;
  }

  header.phiaget-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background-color: #ffffff;
    border-bottom: 1px solid #e2e8f0;
    padding: 1rem 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
  }

  .logo {
    max-height: 48px;
  }

  .user-menu .btn {
    font-size: 0.85rem;
    color: #27384b;
    border-color: #e2e8f0;
    background-color: #f8f9fa;
  }
  
  .user-menu .btn:hover {
    background-color: #e9ecef;
  }
  
  .dropdown-menu {
    font-size: 0.85rem;
  }
  

  .phiaget-title {
    font-size: 1.8rem;
    font-weight: 700;
    color: #27384b;
    margin-left: 1rem;
    margin-bottom: 0;
  }

  .user-info {
    font-size: 0.95rem;
    color: #516979;
    font-weight: 500;
  }

  main.container {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding-top: 1rem;
    padding-bottom: 1rem;
    overflow: hidden;
  }

  .chat-wrapper {
    flex: 1;
    display: flex;
    gap: 2rem;
    overflow: hidden;
  }

  .test-wrapper {
    flex: 1;
    display: flex;
    gap: 2rem;
    overflow: hidden;
  }  

  .chat-column {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 0;
    overflow: auto;
  }

  .test-column {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 0;
    overflow: auto;
  }

  .chat-container {
    flex: 1;
    overflow-y: auto;
    padding: 1rem;
    background-color: #f9fafb;
    border-radius: 0.75rem;
    border: 1px solid #e2e8f0;
    margin-bottom: 1rem;
  }

  .btn-navigation {
    margin-top: 1.5rem;
    display: flex;
    justify-content: space-between;
  }  

  .message-time {
    font-size: 0.75rem;
    color: #999;
  }

  .message {
    margin-bottom: 1rem;
  }

  .message-bubble {
    display: inline-block;
    padding: 0.6rem 1rem;
    border-radius: 1rem;
    max-width: 70%;
    font-size: 0.95rem;
  }

  .message.user {
    text-align: right;
  }

  .message.user .message-bubble {
    background-color: #4cbae7;
    color: white;
  }

  .message.bot {
    text-align: left;
  }

  .message.bot .message-bubble {
    background-color: #e9ecef;
    color: #27384b;
  }

  .btn-primary {
    background-color: #4cbae7;
    border-color: #4cbae7;
    font-weight: 600;
  }

  .btn-primary:hover {
    background-color: #3aaad5;
    border-color: #3aaad5;
  }

  .form-control:focus {
    border-color: #4cbae7;
    box-shadow: 0 0 0 0.2rem rgba(76, 186, 231, 0.25);
  }

  .conversation-summary {
    max-width: 300px;
    word-wrap: break-word;
    overflow-wrap: break-word;
  }
  
  .conversation-summary .list-group-item {
    white-space: normal;
  }

  .list-group-item {
    background-color: #ffffff;
    border-color: #d1d5db;
    color: #555;
  }

  footer {
    position: sticky;
    bottom: 0;
    z-index: 1000;
    background-color: #ffffff;
    text-align: center;
    font-size: 0.9rem;
    color: #888;
    padding: 1rem;
    border-top: 1px solid #e2e8f0;
  }

  footer a {
    text-decoration: none;
    color: #888;
  }

  @media (max-width: 767px) {
    .chat-wrapper {
      flex-direction: column;
    }
    .conversation-summary {
      display: none;
    }
    details.mobile-summary {
      display: block;
    }
  }

  @media (min-width: 768px) {
    details.mobile-summary {
      display: none;
    }
  }