polymer custom responsive element

gistfile1.html

<polymer-element name="rsp-row" attributes="additional-layouts" noscript>
  <template>
    <core-media-query query="min-width: 768px" queryMatches="{{largeScreen}}"></core-media-query>

    <template if="{{largeScreen}}">
      <div horizontal {{additional-layouts}} layout>
        <content></content>
      </div>
    </template>
  </template>
</polymer-element>