.box{
  max-width: 1000px;
  margin: 50px 150px 100px 150px;
  display: grid;
  grid-gap: 10px;
  grid-template-columns: 250px minmax(0,fr);
}

header,nav,main,footer{
border: #352528 5px solid;
}

header{
  grid-row: 1/2;
  grid-column: 1/4;
}

nav{
  grid-row: 3/2;
  grid-column: 3/3;
}

main{
  grid-row: 3/2;
  grid-column: 1/3;
}

footer{
  grid-row: 3/3;
  grid-column: 1/4;
}

body{
    background-image: url("https://karppimann.neocities.org/PlateWithGrid.png");
    background-repeat: repeat-x;
    background-attachment: fixed;
    background-size: 100% 100%;
    margin: 25px;
}