Given the following code:
The .container rule doesn't match the p element. So specificity is irrelevant here. Inheritance and specificity are separate concepts and the only time they interact is when more specific/less specific rules contain declarations with inherit. That is not the case here.
As far as the p element is concerned, only the * rule applies, and the * contains its own font-size declaration, and so the specified font size follows that declaration.
If the * rule didn't have its own font-size declaration, then the p element would inherit from .container.
If you want descendants of .container to take after its font size, you will need an additional .container * rule. Be very careful with the inherit keyword when it comes to relative values, though — you probably meant to keep all descendants the same size, so 1em or 100% is more appropriate here than inherit:
* {
font-size: 18px;
}
.container {
font-size: 50%;
}
.container * {
font-size: 1em;
}
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