CodePen Embed - A "Grid" with Flexbox

<div class="layout">
  <div class="child">a</div>
  <div class="child">a</div>
  <div class="child">a</div>
  <div class="child">a</div>
  <div class="child">a</div>
  <div class="child">a</div>
  <div class="child">a</div>
</div>

.layout {
  display: flex;
  flex-wrap: wrap;
}
.child {
  min-height: 100px;
  background: orange;
  flex: calc(100% / 3);
  text-align: center;
  line-height: 100px;
  border: 5px solid white;
}

* {
  box-sizing: border-box;
}

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This Pen is owned by Chris Coyier on CodePen.

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