How change background color frame around PreferenceFragment?

Question

I use PreferenceActivity with headers(right side) and PreferenceFragment(left side). I change layout in fragment (button and text) but can't change gray frame around.

screenshot: https://i.stack.imgur.com/mdcFS.png

public class PrefActivity extends PreferenceActivity {


@Override
public void onBuildHeaders(List<Header> target) {
    super.onBuildHeaders(target);
    loadHeadersFromResource(R.xml.pref_headers, target);
}


}

public class PrefFragmentMain extends PreferenceFragment {

@Override
public void onCreate(final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    addPreferencesFromResource(R.xml.pref_main);
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View v = super.onCreateView(inflater, container, savedInstanceState); 
   v.setBackgroundColor(getResources().getColor(R.color.color_dark_yellow));
    return v;
}

}