body {
 background: url(behelit.gif);
  color: white;
  font-family: Verdana;
}

.box {
  max-width: 1000px;
  margin: 100px 200px 300px;
  display: grid;
  grid-gap: 10px;
  grid-template-columns: 250px minmax(0, 1fr);
}

nav, main, footer {
  border: purple 2px solid;
}

header {
  grid-row: 1/2;
  grid-column: 1/3;
  color: purple;
  font-family: fantasy;
}

nav {
  grid-row: 2/3;
  grid-column: 1/2;
  height: max-content;
}

footer {
  grid-row: 40/40;
  grid-column: 1/3;
}