:root{--bg:#fff;--text:#333;--text-secondary:#666;--text-muted:#999;--border:#eee;--link:#2563eb;--nav-bg:#15734c;--card-bg:#fff}:root.dark{--bg:#1a1a1a;--text:#e5e5e5;--text-secondary:#aaa;--text-muted:#888;--border:#333;--link:#6ea8fe;--nav-bg:#0d4a2f;--card-bg:#2a2a2a}body,html{margin:0;padding:0}*,:after,:before{box-sizing:border-box}body{background:var(--bg);color:var(--text);transition:background-color .2s,color .2s}