/** Implements methods that access the top-level menu. */
Class BaseLayout {...}

/** Implements methods that access elements of the "Start" page */
Class StartPage extends Base Layout {...}

/** Implements methods that access elements of the "About" page */
Class AboutPage extends Base Layout {...}

/** Implements methods that access the top-level menu. */
Class BaseLayout {...}

/** Implements methods that access elements of the "Start" page */
Class StartPage {
    BaseLayout parent;
    // ...
}

/** Implements methods that access elements of the "About" page */
Class AboutPage {
    BaseLayout parent;
    // ...
}