If you have a browser using an engine with a full `:has()` implementation (WebKit, Chromium) then this is kind of nifty, despite the gross selector hack, if I do say so myself: https://codepen.io/meyerweb/pen/jOQZoaw
(In Gecko, there will be some hover shadows as you mouse around the table, but not the down-and-across effect, due to their partial implementation of `:has()`.)