body {
    font-family: sans-serif;
    background-color: #f3f4f6;
    color: #1f2937;
    margin: 0;
    padding: 0;
    transition: background-color 0.3s, color 0.3s;
  }
  
  .dark-mode {
    background-color: #1f2937;
    color: #f3f4f6;
  }
  
  .header {
    background: #fff;
    padding: 1.5rem;
    box-shadow: 0 1px 4px rgba(0,0,0,0.1);
    text-align: center;
    transition: background 0.3s;
  }
  
  .dark-mode .header {
    background: #374151;
  }
  
  .main {
    padding: 2rem;
    max-width: 800px;
    margin: auto;
  }
  
  section {
    margin-bottom: 3rem;
    animation: fadeIn 0.8s ease-in-out;
  }
  
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
  }
  
  .project {
    background: #fff;
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 1rem;
    box-shadow: 0 1px 4px rgba(0,0,0,0.05);
    transition: transform 0.3s;
  }
  
  .project:hover {
    transform: translateY(-4px);
  }
  
  .dark-mode .project {
    background: #4b5563;
  }
  
  .contact a {
    margin-right: 1rem;
    text-decoration: none;
    color: #2563eb;
    transition: color 0.3s;
  }
  
  footer {
    text-align: center;
    padding: 1rem;
    font-size: 0.9rem;
    color: #6b7280;
    transition: color 0.3s;
  }
  
  .dark-mode footer {
    color: #d1d5db;
  }
  
  #dark-mode-toggle {
    position: fixed;
    top: 1rem;
    right: 1rem;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
  }
  
  .filter-buttons {
    margin-bottom: 1rem;
  }
  
  .filter {
    margin-right: 0.5rem;
    padding: 0.5rem 1rem;
    background-color: #e5e7eb;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background 0.3s;
  }
  
  .filter:hover {
    background-color: #d1d5db;
  }
  
  .dark-mode .filter {
    background-color: #6b7280;
    color: #f9fafb;
  }
  
  .dark-mode .filter:hover {
    background-color: #4b5563;
  }
  
  @keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
  }