<div class="grid">
  <div class="col-span-12">Nav</div>
  <div class="col-span-8 grid">
    <div class="col-span-4">Post</div>
    <div class="col-span-4">Post</div>
    <div class="col-span-4">Post</div>
    <div class="col-span-4">Post</div>
    <div class="col-span-4">Post</div>
    <div class="col-span-4">Post</div>
    <div class="col-span-4">Post</div>
    <div class="col-span-4">Post</div>
    <div class="col-span-4">Post</div>
  </div>
  <div class="col-span-4 grid">
    <div class="col-span-12">Section</div>
    <div class="col-span-12">Section</div>
    <div class="col-span-12">Section</div>
  </div>
  <div class="col-span-12">Footer</div>
</div>
.grid {
  display: grid;
  grid-template-columns: repeat(12, auto);
  gap: 10px;
}

.grid div {
  font-family: Georgia, "Times New Roman", Times, serif;
  font-size: x-large;
  text-align: center;
  padding: 20px;
  border: 1px solid orange;
  background-color: bisque;
}

.col-span-1 {
  grid-column: span 1;
}

.col-span-2 {
  grid-column: span 2;
}

.col-span-3 {
  grid-column: span 3;
}

.col-span-4 {
  grid-column: span 4;
}

.col-span-5 {
  grid-column: span 5;
}

.col-span-6 {
  grid-column: span 6;
}

.col-span-7 {
  grid-column: span 7;
}

.col-span-8 {
  grid-column: span 8;
}

.col-span-9 {
  grid-column: span 9;
}

.col-span-10 {
  grid-column: span 10;
}

.col-span-11 {
  grid-column: span 11;
}

.col-span-12 {
  grid-column: span 12;
}

External CSS

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External JavaScript

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