mdx-deck/templates/basic/theme.js

import theme from 'mdx-deck/themes'

export default {
  ...theme,

  // Customize your presentation theme here.
  //
  // Read the docs for more info:
  // https://github.com/jxnblk/mdx-deck/blob/master/docs/theming.md
  // https://github.com/jxnblk/mdx-deck/blob/master/docs/themes.md

}