Incorrect hover text color bug in the header

[JayanAXHF]

When you go to the header on 3blue1brown.com and hover on the background, the color for the page titles turns grey:

Steps to reproduce

1. Go to 3blue1brown.com.
2. Hover over the header and observe

[vincerubinetti]

Not really a bug but a limitation of CSS at the time. But now this can be fixed with widespread browser support of :has():

.link:hover { color: blue }

header:has(.link:hover) .link:not(:hover) { opacity: 0.5 }