body {
  margin: 0
}

main, nav {
  margin: 0 4em;
}

article {
  margin-top: 6em;
}


p.topbanner {
  margin-top: 0;
}

.topbanner {
  border: 2px dashed black;
  padding: 1em 0.5em;
  background-color: #eee;

}

.flex-plots {
  display: flex;
  flex-wrap: wrap;
  column-gap: 4em;
  row-gap: 1.5em;
}