t, 20px);
  grid-row-gap: 20px;
  grid-column-gap: 20px;
  align-content: space-around;
  justify-content: space-around;
}
.grid > div { background: green; }
</style>
<p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
<div class="block">
    <div style="top: 20px; left: 100px;"></div>
    <div style="top: 20px; left: 180px;"></div>
    <div style="top: 100px; left: 180px;"></div>
    <div style="top: 180px; left: 180px;"></div>
    <div style="top: 260px; left: 20px;"></div>
 