<div class="grid">
   <div class="grid-item">1</div>
   <div class="grid-item">2</div>
   <div class="grid-item">3</div>
   <div class="grid-item">4</div>
   <div class="grid-item">5</div>
   <div class="grid-item">6</div>
   <div class="grid-item">7</div>
   <div class="grid-item">8</div>
   <div class="grid-item">9</div>
   <div class="grid-item">10</div>
   <div class="grid-item">11</div>
</div>

.grid {
  display: grid;
  grid-template-areas: "a b c d d"
                       "f f g d d";
}

.grid-item {
  background: #4fc3f7;
  padding: 1em;
  border: 2px solid #fff;
  text-align:center;
  font-size:35px;
}

.grid-item:nth-child(4) {
  grid-area: d;
}

.grid-item:nth-child(5) {
  grid-area: f;
}