text: import { useAmp } from 'next/amp'
  import Document, { Html, Head, Main, NextScript } from 'next/document'
  
  const AmpTst = () => {
    const isAmp = useAmp()
    return <p>{isAmp ? 'AMP Power!!!' : 'no AMP for you...'}</p>
  }
  
  class MyDocument extends Document {
    static async getInitialProps (ctx) {
      const initialProps = await Document.getInitialProps(ctx)
      return { ...initialProps }
    }
  
    render () {
      return (
        <Html>
          <Head />
          <body>
            <Main />
            <AmpTst />
            <NextScript />
          </body>
        </Html>
      )
    }
  }
  
  export default MyDocument
  