<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>CSS Masking: mask-image: unresovlable mask url</title>
    <link rel="author" title="CJ Ku" href="mailto:cku@mozilla.com">
    <link rel="author" title="Mozilla" href="https://www.mozilla.org">
    <link rel="help" href="https://www.w3.org/TR/css-masking-1/#the-mask-image">
    <link rel="match" href="/css/reference/blank.html">
    <meta name="assert" content="Test checks a mask reference to a none-mask SVG element should be counted as an image layer of transparent black.">
    <svg height="0">
      <clipPath id="clip1">
        <circle cx="50" cy="50" r="25"/>
      </clipPath>
    </svg>
    <style type="text/css">
      div {
        background-color: purple;
        width: 100px;
        height: 100px;
      }

      div.mask-by-reference {
        mask-image: url(#clip1);
      }
    </style>
  </head>
  <body>
    <div class="mask-by-reference"></div>
  </body>
</html>
