[CSS Gap Decorations] unwanted Sub-grid column rule gaps

[bigandy]

I am using a subgrid on the articles to get the content to line up correctly. the bug I am seeing is the empty grid spaces have a gap in them due to the subgrid on the article.

1. Ideally there would be no gaps in the column-rule
2. also no line for any empty grid boxes as mentioned on this issue

My code is here: https://codepen.io/bigandy/pen/vENxYzV

[kbabbitt]

Thanks for the feedback and the code link, that helps a lot.

Couple of observations about this example:

1. I'm happy that the vertical separators being continuous between articles but broken at the row break is working! But I admit I'm unclear on how it's working - with column-rule-break: intersection I would have expected unwanted gaps throughout the layout. Since this is desired behavior I'd prefer to write it down that way; I'm just not sure what to write yet. Admittedly I'm not well versed in subgrid layout, so maybe there's an interaction there I don't know about.

2. In [CSS Gap Decorations] Should we add gap decorations for empty grid areas? #1099 and [CSS Gap Decorations] More control over where rules appear? #1100 the issue authors both expressed preference for gap decoration areas to solve the "empty cells" use case. But because this grid is responsive to container width, I don't see how gap decoration areas could handle it. So maybe we need both gap decoration areas and something to control behavior in gaps adjacent to empty cells.

cc @alisonmaher @oSamDavis @jav099 for their thoughts as well.