|  | <!DOCTYPE html> | 
|  | <html> | 
|  | <meta charset="utf-8"> | 
|  | <title>CSS Multi-column Layout Test: Test the column rules' block-size with nested balancing multicol container</title> | 
|  | <link rel="author" title="Ting-Yu Lin" href="mailto:tlin@mozilla.com"> | 
|  | <link rel="author" title="Mozilla" href="https://www.mozilla.org/"> | 
|  | <link rel="help" href="https://drafts.csswg.org/css-multicol-1/#cf"> | 
|  | <link rel="help" href="https://drafts.csswg.org/css-multicol-1/#column-gaps-and-rules"> | 
|  | <link rel="help" href="https://github.com/w3c/csswg-drafts/issues/2309"> | 
|  | <link rel="match" href="multicol-rule-nested-balancing-001-ref.html"> | 
|  | <meta name="assert" content="This test verifies that the column-rules are extended to the content block-end edges of their corresponding inner and outer multicol container."> | 
|  |  | 
|  | <style> | 
|  | .outer { | 
|  | column-count: 2; | 
|  | column-rule: 6px solid black; | 
|  | width: 400px; | 
|  | height: 250px; | 
|  | } | 
|  | .inner { | 
|  | column-count: 2; | 
|  | column-rule: 3px solid gray; | 
|  | height: 200px; | 
|  | } | 
|  | .outer-block { | 
|  | background-color: lightgreen; | 
|  | height: 200px; | 
|  | } | 
|  | .inner-block { | 
|  | background-color: lightblue; | 
|  | height: 300px; | 
|  | } | 
|  | </style> | 
|  |  | 
|  | <article class="outer"> | 
|  | <div class="outer-block"></div> | 
|  | <article class="inner"> | 
|  | <div class="inner-block"></div> | 
|  | </article> | 
|  | </article> | 
|  | </html> |