| <!DOCTYPE html> | |
| <meta charset="UTF-8"> | |
| <title>CSS Containment Test: 'contain: paint' and margin collapsing</title> | |
| <link rel="author" title="Gérard Talbot" href="http://www.gtalbot.org/BrowserBugsSection/css21testsuite/"> | |
| <link rel="help" href="https://www.w3.org/TR/css-contain-1/#containment-paint"> | |
| <link rel="match" href="reference/contain-paint-ifc-011-ref.html"> | |
| <meta content="This test checks that a block element with 'contain: paint' establishes a new block formatting context which is independent and separate from others. This causes margin collapsing to be ineffective among vertically-adjacent boxes. In this test, the top margin of parent boxes and top margin of their respective first in-flow child do not collapse. Also, in this test, the bottom margin of the last in-flow child of boxes and bottom margin of their respective parent boxes do not collapse." name="assert"> | |
| <meta name="flags" content=""> | |
| <style> | |
| div | |
| { | |
| contain: paint; | |
| margin: 30px 0px; | |
| } | |
| div#grand-grand-parent-orange | |
| { | |
| background-color: orange; | |
| } | |
| div#grand-parent-blue | |
| { | |
| background-color: blue; | |
| } | |
| div#parent-lime | |
| { | |
| background-color: lime; | |
| } | |
| div#collapse-through-child /* margin collapsing through element */ | |
| { | |
| contain: none; | |
| } | |
| </style> | |
| <p>Test passes if there are 5 horizontal stripes across the page in this order (from top to bottom): an orange stripe, a blue stripe, a bright green stripe, a blue stripe and then an orange stripe. | |
| <div id="grand-grand-parent-orange"> | |
| <div id="grand-parent-blue"> | |
| <div id="parent-lime"> | |
| <div id="collapse-through-child"></div> | |
| </div> | |
| </div> | |
| </div> |