:root{--bg:#f3f4f6;--card:#fff;--text:#111827;--muted:#6b7280;--border:#e5e7eb;--accent:#2563eb;--danger:#dc2626;--success:#16a34a}*{box-sizing:border-box}html,body,#root{height:100%}body{background:var(--bg);color:var(--text);margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Cantarell,Noto Sans,sans-serif}.app{flex-direction:column;min-height:100%;display:flex}.navbar{background:var(--card);border-bottom:1px solid var(--border);justify-content:space-between;align-items:center;gap:12px;padding:12px 16px;display:flex;position:sticky;top:0}.navbar a{color:var(--text);font-weight:500;text-decoration:none}.navbar button{border:1px solid var(--border);cursor:pointer;background:0 0;border-radius:8px;padding:6px 10px}.container{width:100%;max-width:900px;margin:0 auto;padding:16px}.card{background:var(--card);border:1px solid var(--border);border-radius:12px;flex-direction:column;gap:10px;padding:16px;display:flex}input{border:1px solid var(--border);font:inherit;border-radius:8px;padding:10px 12px}button{background:var(--accent);color:#fff;cursor:pointer;border:none;border-radius:8px;padding:10px 12px;font-weight:600}.error{color:var(--danger);background:#fee2e2;border:1px solid #fecaca;border-radius:8px;padding:10px}ul{text-align:left;border:1px solid var(--border);background:var(--card);border-radius:12px;padding:12px;list-style:none}li{border-bottom:1px solid var(--border);padding:8px 4px}li:last-child{border-bottom:none}