css/css-grid/abspos/grid-positioned-item-dynamic-change-001.html

<!DOCTYPE html>
<html lang=en class="reftest-wait">
<meta charset="utf-8">
<title>CSS Grid Layout Test: Grid positioned item dynamic change</title>
<link rel="author" title="Manuel Rego Casasnovas" href="mailto:rego@igalia.com">
<link rel="help" href="https://drafts.csswg.org/css-grid-1/#abspos" title="9. Absolute Positioning">
<link rel="match" href="../../reference/ref-filled-green-100px-square.xht">
<meta name="assert" content="This test checks that positioned items can be dynamically changed.">
<style>
.grid {
  display: grid;
  grid: 50px 50px / 50px 50px;
  position: relative;
}

.green {
  background: green;
}

.red {
  background: red;
}

#item {
  position: absolute;
  width: 100%;
  height: 100%;
  grid-column: 1 / 2;
  grid-row: 1 / 2;
}
</style>

<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>

<div class="grid">
  <div class="green"></div>
  <div class="green"></div>
  <div class="green"></div>
  <div class="red"></div>
  <div id="item" class="green"></div>
</div>

<script>
  document.body.offsetLeft;

  var item = document.getElementById("item");
  item.style.gridColumn = "2 / 3";
  item.style.gridRow = "2 / 3";

  document.documentElement.classList.remove('reftest-wait');
</script>

</html>