css/css-scroll-snap/scroll-target-align-003.html

<!DOCTYPE html>
<html>
<title>focus() and snap position with snapping off (y-axis)</title>
<link rel='author' title='Elika J. Etemad' href='http://fantasai.inkedblade.net/contact'>
<link rel='help' href='https://www.w3.org/TR/css-scroll-snap-1/#choosing'>
<link rel='match' href='scroll-target-001-ref.html'>
<meta name="flags" content="may">
<meta name='assert'
      content="Test passes if scroll snapping is honored
               on a scroll container with 'scroll-snap-type: none'
               when scrolling an element into view
               even if that operation is implied (in this case, by .focus()).">
<style type='text/css'>
  .container {
    border: solid blue 4px;
    height: 4em;
    overflow: auto;

    /* to make failing more obvious */
    background: 0 1em / 100% 1em linear-gradient(red, red) repeat-x;
    /* avoid anti-aliasing issues */
    font: 20px/1 sans-serif;
    scrollbar-width: none;
  }
  .container > div, a {
    height: 1em;
    display: block;
    outline: none;
  }
  .container { scroll-padding:  .5em 0 0; } /* set up a snap position      */
  #target    { scroll-margin:   .5em 0 0;
               scroll-snap-align: center; }
  #stripe    { background: green;         } /* color part of the snap area  */
  .fail      { color: red;                } /* make failing more obvious    */

  /* emulate `scrollbar-width: none` for browsers that don't support it yet */
  ::-webkit-scrollbar { display: none; }
</style>

<div id='instructions'>Test passes if there is a green stripe across the second quarter of the box below and no red.</div>

<div class="container">
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div class="fail">FAIL</div>
  <div></div>
  <div id="stripe"></div>
  <a href="" id="target"></a>
  <div></div>
  <div class="fail">FAIL</div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
</div>

<script>
  document.getElementById('target').focus();
</script>