css/css-grid/grid-items/grid-item-containing-block-002.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Grid Layout Test: Grid item sizing</title>
<link rel="author" title="Tomek Wytrebowicz" href="mailto:tomalecpub@gmail.com">
<link rel="help" href="http://www.w3.org/TR/css-grid-1/#grid-items" title="4. Grid Items">
<meta name="assert" content="A grid item is sized within the containing block defined by its grid area">
<link rel="match" href="../../reference/ref-filled-green-100px-square.xht">
<style>
    #grid {
        display: grid;
        width: 200px;
        height: 200px;
        grid-template-rows: 50%;
        grid-template-columns: 50%;
    }

    #test-overlapped-red {
        background-color: red;
        width: 100%;
        height: 100%;
    }

    #test-overlapping-green {
        background-color: green;
        width: 100px;
        height: 100px;
    }
</style>
<body>
    <p>Test passes if there is a filled green square and <strong>no red</strong>.</p>

    <div id="grid">
        <div id="test-overlapped-red">
            <div id="test-overlapping-green"></div>
        </div>
    </div>
</body>