| <!DOCTYPE html> | |
| <style> | |
| div { | |
| border: 2px solid black; | |
| padding: 5px 0; /* No horizontal padding as outline-offset is not affected by it and span simulates it */ | |
| font-size: 16px; | |
| } | |
| span { | |
| display: block; | |
| /* 3/6px offset for border */ | |
| height: 2px; | |
| width: calc(100% - 20em + 6px); | |
| margin: -1px calc(10em - 3px); /* -1px vertical to remove height of span from div height */ | |
| background: red; | |
| } | |
| </style> | |
| <p>PASS if there is a thin red line in the middle of the box.</p> | |
| <div> | |
| <span></span> | |
| </div> |