body {
  padding: 10% 10% 0;
  margin-top: -90px;
}

h1 {   font-family: monospace;

 }

#editor {
  border: thin solid black;
  font-family: monospace;
  font-size: large;
}

#editor > div {
  counter-increment: lineno;
  display: flex;
}

#editor > div::before {
  content: counter(lineno);
  width: 2em;
  margin-right: 1em;
  flex-shrink: 0;
  text-align: right;
}


.article {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  padding:5% 20% 0;
}