:root{font-family:Inter,system-ui,Arial,sans-serif}body{margin:0;background:#f8fafc;color:#111827}.container{max-width:900px;margin:0 auto;padding:24px}nav{display:flex;gap:16px;margin-bottom:20px}nav a{color:#2563eb;text-decoration:none}input{display:block;margin:8px 0;padding:8px;width:280px}button{padding:8px 12px;margin-right:8px}pre{background:#0f172a;color:#e2e8f0;padding:12px;overflow:auto}.row{display:flex;gap:8px;flex-wrap:wrap;margin:8px 0}.success{color:#166534}.error{color:#b91c1c}details{margin-top:12px}