Result Size: 300 x 150
x
 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>Grid in CSS</title>
  <style>
    .container {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      grid-template-rows: repeat(2, minmax(3rem, auto));
      gap: 5px;
      width: 30rem;
    }
    .item {
      background: lightgray;
      text-align: center;
    }
    .item1 {
      background-color:skyblue;
      grid-row: 2;
      grid-column: 3/5;
    }
  </style>
 </head>
<body>
  <div class="container">
    <div class="item item1">1</div>
    <div class="item item2">2</div>
    <div class="item item3">3</div>
    <div class="item item4">4</div>
    <div class="item item5">5</div>
    <div class="item item6">6</div>
    <div class="item item7">7</div>
    <div class="item item8">8</div>
  </div>
</body>
</html>