id="app">
    <core-drawer-panel>
      <core-header-panel drawer>
        <core-toolbar>Menu</core-toolbar>
        <core-menu selected="{{page}}" valueattr="data-category">
          <core-item data-category="home" label="Home"></core-item>
          <core-item data-category="portfolio" label="Portfolio"></core-item>
          <core-item data-category="contact" label="Contact"></core-item>
        </core-menu>
      </core-header-panel>
      <core-header-panel main>
        <core-toolbar>
          <pape