body {
  margin: 0;
  }


.grid-container{
    display: grid;
    grid-template-columns: 1fr 2fr 1fr;
    grid-template-rows: 1fr 900px 1fr;
}

.item1 {
    grid-column: span 3 / span 3;
    padding: 2em;
    color: white;
    border: 2px solid black;
    background-color: grey;
    text-align: center;
}

.item2 {
    grid-column: 2 / span 2;
    grid-row:  2 / span 2;
    grid-column-start: 2;
    grid-row-start: 2;
    padding: 2em;
    color: white;
    border: 2px solid black;
    background-color: grey;
    text-align: center;
}

.item3 {
    grid-row: 2 / span 2;
    grid-column-start: 1;
    grid-row-start: 2;
    color: white;
    border: 2px solid black;
    background-color: grey;
    text-align: center;
}
.nested{
  display: grid;
  grid-template-columns: repeat(2,1fr);
  grid-template-rows: repeat(2,100px);
  margin: 0;
  padding: 20px;
  gap: 10px;
}
.nested p{
  border: 2px solid black;
  background-color: orange;
  color: black;
  text-align: center;
}
.scrollbar{
    display: grid;
    background-color: white;
    grid-template-columns: 500px;
    grid-template-rows: 100px;
    border: 2px solid black;
    padding: 0;
    margin: 0;
    overflow: auto;
}
.scrollbar p{
    margin:0;
    padding: 20px;
    color: black;
}