| <!DOCTYPE html> |
| <title>position:sticky elements should not affect the flow position of other elements</title> |
| <link rel="help" href="https://www.w3.org/TR/css-position-3/#sticky-pos" /> |
| <meta name="assert" content="This test checks that position:sticky elements do not affect the flow position of other elements" /> |
| |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| |
| <style> |
| .scroller { |
| position: relative; |
| height: 200px; |
| width: 100px; |
| overflow: scroll; |
| } |
| |
| #sticky { |
| background-color: green; |
| position: sticky; |
| top: 150px; |
| } |
| |
| #before { |
| background-color: fuchsia; |
| } |
| |
| #after { |
| background-color: orange; |
| } |
| |
| .box { |
| height: 50px; |
| width: 50px; |
| } |
| |
| .padding { |
| height: 500px; |
| } |
| </style> |
| |
| <div class="scroller"> |
| <div id="before" class="box"></div> |
| <div id="sticky" class="box"></div> |
| <div id="after" class="box"></div> |
| <div class="padding"></div> |
| </div> |
| |
| <script> |
| test(() => { |
| // The sticky element is pushed to be stuck 150 pixels from the top. |
| assert_equals(sticky.offsetTop, 150); |
| |
| // Neither 'before' or 'after' should be affected by the change in the sticky |
| // element's location. |
| assert_equals(before.offsetTop, 0); |
| assert_equals(after.offsetTop, before.clientHeight + sticky.clientHeight); |
| }, 'sticky offset should not affect the position of other elements.'); |
| </script> |
