I hear you, though one of the newest CSS features does in fact support this. It's called the anchor positioning API: https://developer.chrome.com/blog/anchor-po

I hear you, though one of the newest CSS features does in fact support this. It's called the anchor positioning API: https://developer.chrome.com/blog/anchor-positioning-api https://developer.chrome.com/blog/anchor-positioning-api The problem with this specific API is that it depends on source order. To have element-b anchored to element-a, element-a must come first in source. I'm not really sure if it was designed that way or just implemented that way in Chrome, but it's the behavior I experienced when I played around with it.