* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
  }
  
  html {
    font-size: 20px;
    line-height: 1.44;
    min-height: 100%;
  }

  #nav {
    display: flex;
    justify-content: space-between;
    margin: 1.44rem;
  }

  header {
    margin: 1.44rem;
  }
  iframe {
    display: block;
    margin: 1.44rem;
    margin-top: 3em;
  }