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


<span class="nope">🚫 &nbsp; Sorry, but CSS Grid is unsupported in your browser.</span>

body {
  padding-top: 40px;
  background: #f5f7f8;
}

.grid-1 {
  display: grid;
  width: 100%;
  max-width: 750px;
  margin: 0 auto;
  grid-template-columns: repeat(3, 33.33%);
  grid-gap: 20px;
}

/* items */

.grid-1 div {
  color: white;
  font-size: 20px;
  padding: 20px;
  }

/* specific item styles */

.item-1 {
  background: #b03532;
}
.item-2 {
  background: #33a8a5;
}
.item-3 {
  background: #30997a;
}
.item-4 {
  background: #6a478f;
}
.item-5 {
  background: #da6f2b;
}
.item-6 {
  background: #3d8bb1;
}
.item-7 {
  background: #e03f3f;
}
.item-8 {
  background: #59a627;
}
.item-9 {
  background: #4464a1;
}


/* warn against lack of browser support */

.nope {
  display: block;
  color: white;
  background: orange;
  text-align: center;
  padding: 10px;
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
} 

@supports (display: grid) {
  .nope {
    display: none;
  } 
}