:root{--bg:#f5f4f0;--panel:#fff;--border:#dedcd5;--text:#1f1f1f;--muted:#6b6b6b;--accent:#2f6fdb;--accent-soft:#e6eefb;--danger:#b3261e;color:var(--text);background:var(--bg);font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;font-size:14px}*{box-sizing:border-box}body{margin:0}h2{text-transform:uppercase;letter-spacing:.06em;color:var(--muted);margin:0 0 8px;font-size:12px}button{font:inherit;color:inherit;background:var(--panel);border:1px solid var(--border);cursor:pointer;border-radius:6px;padding:4px 10px}button:hover:not(:disabled){border-color:var(--accent)}button:disabled{opacity:.5;cursor:default}button.primary{background:var(--accent);border-color:var(--accent);color:#fff}.muted{color:var(--muted)}.small{font-size:12px}.app{grid-template-columns:280px minmax(420px,600px) minmax(380px,1fr);gap:16px;max-width:1500px;height:100vh;margin:0 auto;padding:16px;display:grid}.panel{background:var(--panel);border:1px solid 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