Header {
  margin: 1rem 0 0 1rem

  nav {
    display: flex
    align-items: center

    position: fixed
    top: 0
    left: 0
    background: #fff
    width: 100%
    padding: 1rem

    a, div {
      color: #222
      margin-right: 1rem

      :hover {
        text-decoration: underline
      }
    }

    div.back {
      border: 1px solid #ddd
      padding: 0 0.2em;
      font-size: 1.4rem;
      border-radius: 4px

      :hover {
        text-decoration: none
        border-color: #222 
      }
    }
  }

  h1 { 
    margin-top: 4rem

  }
}