:root {
      --bg-color: #121212;
      --text-color: #f5f5f5;
      --accent: #00bcd4;
      --card-bg: #1e1e1e;
    }
    body.light {
      --bg-color: #ffffff;
      --text-color: #222222;
      --accent: #673ab7;
      --card-bg: #f4f4f4;
    }
    body {
      font-family: 'Segoe UI', sans-serif;
      margin: 0; padding: 0;
      background: var(--bg-color);
      color: var(--text-color);
      transition: background 0.3s ease, color 0.3s ease;
    }
    header {
      text-align: center;
      padding: 3rem;
      background: linear-gradient(135deg, #00bcd4, #673ab7);
      color: white;
    }
    header img {
      width: 120px; border-radius: 50%; border: 3px solid white;
      transition: transform 0.3s ease;
    }
    header img:hover { transform: scale(1.1); }
    section { padding: 2rem; max-width: 900px; margin: auto; }
    h2 { color: var(--accent); }
    .projects {
      display: flex; gap: 1.5rem; flex-wrap: wrap; justify-content: center;
    }
    .project-card {
      background: var(--card-bg);
      border-radius: 12px;
      padding: 1.5rem;
      width: 260px;
      box-shadow: 0 4px 10px rgba(0,0,0,0.4);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
    }
    .project-card:hover {
      transform: translateY(-8px);
      box-shadow: 0 8px 20px rgba(0,0,0,0.6);
    }
    .project-card a {
      color: var(--accent);
      text-decoration: none;
      font-weight: bold;
    }
    footer {
      text-align: center;
      padding: 1.5rem;
      background: #0d0d0d;
      color: #aaa;
    }
    footer a { color: var(--accent); text-decoration: none; }
    .toggle-btn {
      margin-top: 1rem;
      padding: 0.5rem 1rem;
      border: none;
      border-radius: 6px;
      cursor: pointer;
      background: var(--accent);
      color: white;
      font-weight: bold;
    }