<div class="box row">
  <div></div>
  <div></div>
  <div></div>
  <div></div>
</div>

<div class="box column">
  <div></div>
  <div></div>
  <div></div>
  <div></div>
</div>

<div class="clear"></div>

<div class="note row">
  <pre><code>grid-auto-flow: <strong>row</strong>;</code></pre>
</div>
<div class="note column">
  <pre><code>grid-auto-flow: <strong>column</strong>;</code></pre>
</div>
* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
}

.box {
  width: 50%;
  padding: 6px;
  display: grid;
  height: 175px;
  grid-auto-flow: row;
  grid-gap: 2px;
  float: left;
}

.box.column {
  grid-auto-flow: column;
  float: right;
}

.box > div {
  background-color: tomato;
}

.clear {
  clear: both;
}

.note {
  width: 50%;
  font-size: 18px;
  font-family: monospace;
  text-align: center;
  line-height: 5;
}

.note.row {
  float: left;
}

.note.column {
  float: right;
}

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