Blitz - WPT: grid-block-start.html

wpt / css / css-box / margin-trim / computed-margin-values / grid-block-start.html

Data from commit:
708eb61 WPT runner: support mismatch reftests and multiple rel=match links (#665) (2026-08-09)

Subtest	Status	Message
grid > item 1	FAIL	assert_equals: data-expected-margin-top expected 0 got 195.5
grid > item 2	FAIL	assert_equals: data-expected-margin-top expected 0 got -30
grid > item 3	PASS
grid > item 4	PASS

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/css/css-box/margin-trim/computed-margin-values/grid-block-start.html

<!DOCTYPE html>
<html>
<head>
<link rel="author" title="Sammy Gill" href="mailto:sammy.gill@apple.com">
<link rel="help" href="https://drafts.csswg.org/css-box-4/#margin-trim-grid">
<meta name="assert" content="Grid items with trimmed block start margins should be reflected in computed style">
<style>
grid {
    display: grid;
    width: min-content;
    border: 1px solid black;
    grid-template-columns: auto auto;
    margin-trim: block-start;
}
item {
    display: block;
    width: 50px;
    height: 50px;
    background-color: green;
}
.locked-location {
    grid-row: 1;
    grid-column: 2;
}
item:nth-child(1) {
    margin-block-start: 50%;
}
item:nth-child(2) {
    margin-block-start: -30px;
}
item:nth-child(3) {
    margin-block-start: 10px;
}
item:nth-child(4) {
    margin-block-start: 10px;
}
</style>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/check-layout-th.js"></script>
</head>
<body onload="checkLayout('grid > item')">
    <div id="target">
    <grid>
        <item class="locked-location" data-expected-margin-top="0"></item>
        <item data-expected-margin-top="0"></item>
        <item data-expected-margin-top="10"></item>
        <item data-expected-margin-top="10"></item>
    </grid>
    </div>
</body>
</html>