und: #F69;
}

.element-d {
  grid-column-start: 1;
  grid-column-end: 2;
  grid-row-start: 3;
  grid-row-end: 4;
  background: #9F6;
}

.element-e {
  grid-column-start: 3;
  grid-column-end: 4;
  grid-row-start: 3;
  grid-row-end: 4;
  background: #96F;
}

.element-f {
  grid-column-start: 5;
  grid-column-end: 6;
  grid-row-start: 3;
  grid-row-end: 4;
  background: #F96;
}
</style>
<summary class="grid-container">
  <div class="grid-element element-a">A</div>
  <div class="grid-element element-b">B</div>