* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  
  body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: #333;
    background: #f5f5f5;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
  }
  #alert {
    position: fixed;
    top: 15px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 9999;
    min-width: 220px;
    max-width: 70vw;
    text-align: center;
    font-size: 1.1em;
    pointer-events: none;
    opacity: 0.98;
    transition: opacity 0.3s;
  }
  .skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: #000;
    color: #fff;
    padding: 8px;
    text-decoration: none;
  }
  
  .skip-link:focus {
    top: 0;
  }
  
  header {
    background: #2c3e50;
    color: #fff;
    padding: 1rem 0;
    margin: 0 -1rem 2rem;
  }
  
  header h1 {
    text-align: center;
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
  }
  
  nav ul {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
  }
  
  nav a {
    color: #fff;
    text-decoration: none;
    padding: 0.25rem 0.5rem;
  }
  
  nav a:hover {
    background: rgba(255,255,255,0.1);
    border-radius: 4px;
  }
  
  /* Sections */
  section {
    background: #fff;
    padding: 1.5rem;
    margin-bottom: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  }
  
  h2 {
    margin-bottom: 1rem;
    color: #2c3e50;
    font-size: 1.3rem;
  }
  
  form > div {
    margin-bottom: 1rem;
  }
  
  label {
    display: block;
    margin-bottom: 0.25rem;
    font-weight: 500;
  }
  
  input, select {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 1rem;
  }
  
  input[type="checkbox"] {
    width: auto;
    margin-right: 0.5rem;
  }
  
  button {
    background: #3498db;
    color: #fff;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    margin-right: 0.5rem;
  }
  
  button:hover {
    background: #2980b9;
  }
  
  button[type="button"] {
    background: #95a5a6;
  }
  
  button[type="button"]:hover {
    background: #7f8c8d;
  }
  
  /* Table */
  table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
  }
  
  th, td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid #ddd;
  }
  
  th {
    background: #ecf0f1;
    font-weight: 600;
  }
  
  /* Error messages */
  .error {
    color: #e74c3c;
    font-size: 0.875rem;
    display: block;
    margin-top: 0.25rem;
  }
  
  /* Footer */
  footer {
    text-align: center;
    padding: 1rem;
    color: #7f8c8d;
    margin-top: 2rem;
  }
  
  /* Responsive */
  @media (max-width: 768px) {
    nav ul {
      flex-direction: column;
      align-items: center;
    }
    
    table {
      font-size: 0.875rem;
    }
    
    th, td {
      padding: 0.5rem;
    }
    
    button {
      display: block;
      width: 100%;
      margin-bottom: 0.5rem;
    }
  }