body {
  padding: 0;
}

code {
  vertical-align: middle;
}

aside {
  display: flex;
  flex-direction: column;
  box-sizing: border-box;
  height: 100%;
  width: 30em;
  position: fixed;
  z-index: 1;
  top: 0;
  left: 0;
  overflow-x: hidden;
  padding: 2em 1em 2em 2em;
  border-right: 1px solid grey;
}

aside nav {
  display: flex;
  flex-direction: column;
  flex-grow: 1;
}

main {
  margin-left: 30em;
  padding: 2em;
}