:root{--bg:#fff;--bg-secondary:#f9fafb;--text:#111827;--text-muted:#6b7280;--border:#e5e7eb;--primary:#1b4fd8;--card-bg:#fff}[data-theme=dark]{--bg:#0f172a;--bg-secondary:#1e293b;--text:#f1f5f9;--text-muted:#94a3b8;--border:#334155;--primary:#3b6ff5;--card-bg:#1e293b}*{box-sizing:border-box;margin:0;padding:0}body{background:var(--bg);color:var(--text);font-family:sans-serif;transition:background .2s,color .2s}input{background:var(--bg);color:var(--text);border:1px solid var(--border)}button{cursor:pointer}a{text-decoration:none}