Gatsby, styled-components Theme demo

Demo using Gatsby, styled-components, and wrapping the root element to use ThemeProvider

Setup

// gastby-browser.js
import React from 'react'
import { ThemeProvider } from 'styled-components'

const theme = {
  main: '#c6797e',
}
export const wrapRootElement = ({ element }) => (
  <ThemeProvider theme={theme}>{element}</ThemeProvider>
)

// src/components/layout.js
import React from 'react'
import PropTypes from 'prop-types'
import { useStaticQuery, graphql } from 'gatsby'
import styled from 'styled-components'
import Header from './header'
import './layout.css'

const Container = styled.div`
  background-color: ${props => props.theme.main};
  margin: 0 auto;
  max-width: 960px;
  padding: 0px 1.0875rem 1.45rem;
  padding-top: 0;
`

const Layout = ({ children }) => {
  const data = useStaticQuery(graphql`
    query SiteTitleQuery {
      site {
        siteMetadata {
          title
        }
      }
    }
  `)

  return (
    <>
      <Header siteTitle={data.site.siteMetadata.title} />
      <Container>
        <main>{children}</main>
        <footer>
          © {new Date().getFullYear()}, Built with
          {` `}
          <a href="https://www.gatsbyjs.org">Gatsby</a>
        </footer>
      </Container>
    </>
  )
}

Layout.propTypes = {
  children: PropTypes.node.isRequired,
}

export default Layout