:root {
    --bg: #0f1115;
    --card: #171a21;
    --text: #e6e6e6;
    --muted: #9aa0a6;
    --accent: #4da3ff;
    --border: #2a2f3a;
  }
  
  [data-theme="light"] {
    --bg: #ffffff;
    --card: #f4f6f8;
    --text: #1a1a1a;
    --muted: #555;
    --accent: #0066cc;
    --border: #ddd;
  }
  
  * {
    box-sizing: border-box;
  }
  
  body {
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
      Roboto, Ubuntu, Arial, sans-serif;
    line-height: 1.6;
    transition: background 0.25s ease, color 0.25s ease;
  }
  
  .container {
    max-width: 900px;
    padding: 2rem 1.5rem;
    margin: 0 auto;
  }
  
  .header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
  }
  
  .subtitle {
    color: var(--muted);
    margin-top: 0.5rem;
  }
  
  button {
    background: none;
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 0.4rem 0.8rem;
    cursor: pointer;
    transition: background 0.2s ease, color 0.2s ease;
  }
  
  button:hover {
    background: var(--card);
  }
  
  section {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 1.5rem;
    margin-bottom: 2rem;
    transition: background 0.25s ease;
  }
  
  h2 {
    margin-top: 0;
  }
  
  .projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1rem;
  }
  
  .project-card {
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1rem;
  }
  
  .project-card h3 {
    margin-top: 0;
  }
  
  a {
    color: var(--accent);
    text-decoration: none;
  }
  
  a:hover {
    text-decoration: underline;
  }
  
  .muted {
    color: var(--muted);
  }
  
  .footer {
    text-align: center;
    color: var(--muted);
    font-size: 0.85rem;
  }