| <!DOCTYPE html> |
| <title>Test that @container-dependent elements respond to iframe size changes</title> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <style> |
| iframe { |
| width: 200px; |
| height: 40px; |
| } |
| </style> |
| <iframe id=iframe srcdoc=" |
| <style> |
| div#container { |
| contain: size layout; |
| height: 20px; |
| } |
| div#child { color: red; } |
| @container (min-width: 300px) { |
| div#child { color: green; } |
| } |
| </style> |
| <div id=container> |
| <div id=child>Test</div> |
| </div> |
| "></iframe> |
| <script> |
| |
| function waitForLoad(w) { |
| return new Promise(resolve => w.addEventListener('load', resolve)); |
| } |
| |
| promise_test(async () => { |
| await waitForLoad(window); |
| let inner_div = iframe.contentDocument.querySelector('div#child'); |
| assert_equals(getComputedStyle(inner_div).color, 'rgb(255, 0, 0)'); |
| |
| iframe.style = 'width:400px'; |
| assert_equals(getComputedStyle(inner_div).color, 'rgb(0, 128, 0)'); |
| }) |
| </script> |
