text: import React from 'react'
  import { useStaticQuery, Link, graphql } from "gatsby"
  
  const Header = () => {
    const data = useStaticQuery(
      graphql`
        query {
          site {
            siteMetadata {
              title
            }
          }
        }
      `
    )
    
    return (
      <header>
        <h2>{data.site.siteMetadata.title}</h2>
        <nav>
          <ul>
            <li>
              <Link to="/">top</Link>
            </li>
            <li>
              <Link to="/about">about</Link>
            </li>
          </ul>
        </nav>
      </header>
    )
  }
  
  export default Header