| <style> | |
| div { | |
| position: absolute; | |
| width: 100px; | |
| height: 100px; | |
| background-color: green; | |
| --valid-fallback: 100px; | |
| top: env(some-unknown-name, var(--valid-fallback)); | |
| left: env(--some-invalid-name, var(--valid-fallback)); | |
| } | |
| </style> | |
| <body> | |
| <div></div> | |
| <p>The box should be at 100, 100.</p> | |