testing/web-platform/tests/css/css-backgrounds/background-attachment-350.html
author Lando <lando@lando.test>
Fri, 11 Jul 2025 04:32:24 +0000 (7 minutes ago)
changeset 796014 f14d1c1492bc6791542a001365abbca4bd9b28db
parent 606595 895e9f55c489ee2cc6e5bb3b1039f863e5b72809
permissions -rw-r--r--
Merge autoland to mozilla-central
<!DOCTYPE html>

  <meta charset="UTF-8">

  <title>CSS Background and Borders Test: 'background-attachment: local' and 'overflow: hidden'</title>

  <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/">
  <link rel="help" href="http://www.w3.org/TR/css3-background/#the-background-attachment">
  <link rel="match" href="reference/ref-if-there-is-no-red.xht">

  <!--

  More info:

  Re: [css3-background] background-attachment: local
  http://lists.w3.org/Archives/Public/www-style/2013May/0542.html

  -->

  <meta content="This test checks that when an element has 'background-attachment: local', then the background image is fixed with regard to what is the element's scrollable area and not to its viewport. In this test, what would be the scrollable area for the div element is where the red square is and such area is clipped due to 'overflow: hidden'." name="assert">

  <style>
  div
    {
      background-attachment: local;
      background-image: url("support/100x100-red.png");
      background-position: bottom right;
      background-repeat: no-repeat;
      font-size: 100px;
      line-height: 1;
      height: 100px;
      overflow: hidden;
      width: 100px;
    }
  </style>

  <body>

  <p>Test passes if there is <strong>no red</strong>.

  <div id="target">&nbsp;&nbsp;<br>&nbsp;&nbsp;</div>

  <!--

(0px, 0px)              (200px, 0px)
  +.......................+
  |+..........+           |
  || +......+ |           |
  || |  red | |           | <== bottom right of scrolling box
  || |square| |           |     when background-image dimensions
  || |      | |           |     are the same as the element's
  || +......+ |           |     viewport dimensions
   +..........+           |
  |                       |
  |               +......+|
  |               |  red || <== bottom right of scrollable area
  |               |square||     which is outside of the viewport
  |               |      ||     area and which is clipped due
  |               +......+|     to 'overflow: hidden'
  +.......................+
(0px, 200px)            (200px, 200px)

  -->