TheGame/packages/metamaps/pages/_document.tsx

import Document, { DocumentContext, DocumentInitialProps } from 'next/document'
import { ServerStyleSheet } from 'styled-components'

export default class WebAppDocument extends Document {
  static async getInitialProps(ctx: DocumentContext): Promise<DocumentInitialProps> {
    const sheet = new ServerStyleSheet();
    const originalRenderPage = ctx.renderPage;

    try {
      ctx.renderPage = () =>
      originalRenderPage({
        enhanceApp: App => props => sheet.collectStyles(<App {...props} />),
      })

      const initialProps = await Document.getInitialProps(ctx)
      return {
        ...initialProps,
        styles: (
          <>
            {initialProps.styles}
            {sheet.getStyleElement()}
          </>
        ),
      }
    } finally {
      sheet.seal()
    }
  }
}