| <!DOCTYPE html> | |
| <html> | |
| <head> | |
| <style> | |
| dialog { | |
| visibility: hidden; | |
| } | |
| ::backdrop { | |
| position: absolute; | |
| top: 100px; | |
| left: 100px; | |
| height: 100px; | |
| width: 100px; | |
| background-color: red; | |
| } | |
| .green::backdrop { | |
| background-color: green; | |
| } | |
| </style> | |
| </head> | |
| <body> | |
| Test dynamic changes to ::backdrop style. The test passes if there is a green box below. | |
| <dialog></dialog> | |
| <script> | |
| dialog = document.querySelector('dialog'); | |
| dialog.showModal(); | |
| dialog.classList.add('green'); | |
| </script> | |
| </body> | |
| </html> |