NotionNext/themes/gitbook/components/FloatTocButton.js

import { useGitBookGlobal } from '../LayoutBase'

export default function FloatTocButton () {
  const { tocVisible, changeTocVisible } = useGitBookGlobal()

  const toggleToc = () => {
    changeTocVisible(!tocVisible)
  }

  return (
    <div
      onClick={toggleToc}
      className={ 'text-black flex justify-center items-center dark:text-gray-200 dark:bg-hexo-black-gray py-2 px-2'
      }
    >
      <a
        id="darkModeButton"
        className={'fa-list-ol cursor-pointer fas hover:scale-150 transform duration-200'}
      />
    </div>
  )
}