:root{--bg:#0f1115;--surface:#1a1d24;--text:#f0f2f6;--muted:#8a93a3;--accent:#4dd0a8;--correct:#2ecc71;--wrong:#e74c3c;--font-display:ui-monospace, "SF Mono", Menlo, Consolas, monospace;--font-ui:system-ui, -apple-system, "Segoe UI", Roboto, sans-serif}*{box-sizing:border-box}html,body{background:var(--bg);min-height:100vh;color:var(--text);font-family:var(--font-ui);-webkit-font-smoothing:antialiased;margin:0;padding:0}#app{min-height:100vh}h1,h2,h3{margin:0}button{font-family:inherit}