What is the use of this code

HTML-CSS
1

Tell us what’s happening:
hello
i understood the code here
but what is the use of this code ???
i dont find any change in the preview

Thanks !

Your code so far


<style>
.item1{background:LightSkyBlue;}
.item2{background:LightSalmon;}
.item3{background:PaleTurquoise;}
.item4{background:LightPink;}

.item5 {
  background: PaleGreen;
  /* Only change code below this line */

  
  /* Only change code above this line */
}

.container {
  font-size: 40px;
  min-height: 300px;
  width: 100%;
  background: LightGray;
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  grid-template-rows: 1fr 1fr 1fr;
  grid-gap: 10px;
  grid-template-areas:
    "header header header"
    "advert content content"
    "footer footer footer";
}
</style>

<div class="container">
<div class="item1">1</div>
<div class="item2">2</div>
<div class="item3">3</div>
<div class="item4">4</div>
<div class="item5">5</div>
</div>

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.116 Safari/537.36 Edg/83.0.478.61.

Challenge: Place Items in Grid Areas Using the grid-area Property

Link to the challenge:

2

You didn’t change anything in between “Only change code below this line” and “Only change code above this line”.