content: import React from 'react'
  import ReactDOM from 'react-dom/server'
  import Helmet from 'react-helmet'
  
  export function initHead(args) {
    const { title, description, style, script } = args
    // NOTE: server rendered css will be removed and changed by client after ssr, see client.js
    let helmet = ReactDOM.renderToString(
      <Helmet
        title={title}
        meta={[
          {name: 'charset', content: 'utf-8'},
          {name: 'description', content: description},
        ]}
        style={[
          {type: 'text/css', id: 'server-rendered-css', cssText: style},
        ]}
        script={[
          {type: 'text/javascript', async: true, src: script},
        ]}
      />
    )
    helmet = Helmet.rewind()   // or will memory leak
    return helmet
  }
  