css/css-ui/outline-016.html

<!doctype html>
<html lang=en>
  <meta charset=utf-8>
  <title>CSS-UI test: outline-offset width negative values — long box</title>
  <link rel="author" title="Florian Rivoal" href="http://florian.rivoal.net">
  <meta name=flags content="should">
  <meta name=assert content="Negative values on outline-offset should not cause the height and the width of outside of the shape drawn by the outline to become smaller than twice the computed value of the outline-width property, applying this constrain separately for each shape if there are several shapes.">
  <link rel="match" href="../reference/ref-filled-green-100px-square.xht">
  <link rel=help href="https://drafts.csswg.org/css-ui-3/#outline-props">
<link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
<style>
span {
  outline: solid green 25px;
  outline-offset: -35px; /* Any value that makes sure the outlines collide ( < -25px )
                            would make the test valid,
                            -35px is just one such value that happens to make the failures pretty.
                            I recommend looking at this test in as many UAs as possible,
                            the results are quite astonishing.
			  */
  color: red;
}
div {
  width: 50px;
  height: 50px;
  padding: 25px;
  background: green;
  line-height: 25px;
  font-size: 25px;
  font-family: Ahem;
}
</style>

  <p>Test passes if there is a filled green square and <strong>no red</strong>.</p>
  <div><span>xx<br>xx</span></div>