text: import Document, { Head, Main, NextScript } from 'next/document'
  import { ServerStyleSheet } from 'styled-components'
  
  const description = 'an implementation of 3GPP EPC(MME, SGW, PGW, HSS)'
  
  export default class MyDocument extends Document {
    render () {
      const sheet = new ServerStyleSheet()
      const main = sheet.collectStyles(<Main />)
      const styleTags = sheet.getStyleElement()
      return (
        <html>
          <Head>
            <title>Open5GS</title>
  
            <meta charSet="utf-8" />
            <meta httpEquiv="X-UA-Compatible" content="IE=edge,chrome=1" />
            <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=no" />
  
            <meta name="author" content="Open5GS" />
            <meta name="description" content={description} />
  
            <link rel='icon' href='/static/favicon.ico'/>
            <link rel="stylesheet" type="text/css" href="/static/css/bootstrap.min.css" />
            <link rel="stylesheet" type="text/css" href="/static/css/nprogress.css" />
            <link rel="stylesheet" type="text/css" href="/static/css/index.css" />
            {styleTags}
          </Head>
          <body>
            <div className='root'>
              {main}
            </div>
            <NextScript />
          </body>
        </html>
      )
    }
  }
  