chromium/third_party/blink/web_tests/external/wpt/css/filter-effects/filter-region-negative-positioned-child-001.html

<!DOCTYPE html>
<title>SVG Filters: CSS reference filters with negative positioned children</title>
<link rel="help" href="https://drafts.fxtf.org/filter-effects/#FilterProperty">
<link rel="help" href="https://drafts.fxtf.org/filter-effects/#ColorInterpolationFiltersProperty">
<link rel="help" href="https://drafts.fxtf.org/filter-effects/#feColorMatrixElement">
<link rel="help" href="https://bugs.chromium.org/p/chromium/issues/detail?id=638091">
<link rel="match" href="reference/filter-region-negative-positioned-child-001-ref.html">
<meta name="assert" content="CSS reference filters with negative positioned children"/>
<svg xmlns="http://www.w3.org/2000/svg" width="0" height="0" version="1.1">
  <defs>
    <filter id="f1" color-interpolation-filters="sRGB">
      <feColorMatrix type="matrix" values="-1 0 0 0 1  0 -1 0 0 1  0 0 -1 0 1  0 0 0 1 0"/>
    </filter>
  </defs>
</svg>
<style>
.box {
  width: 100px;
  height: 100px;
  position: absolute;
}
.green {
  background-color: green;
}
.blue {
  background-color: blue;
}
.above {
  top: -100px;
}
.parent {
  filter: url(#f1);
  background-color: white;
  position: relative;
  top: 100px;
}
</style>
<div class="parent">
<div class="green box"></div>
<div class="blue box above"></div>
</div>