:has() and
descendant selector (space)

.first1
.second1

:has() and
child selector (>)

.first2
.second2

:has() and
adjacent sibling selector (+)

.first3
.second3

:has() and
general sibling selector (-)

.first4
.third4
.second4

:has() and combinators
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descendant selector (space)
child selector (>)
adjacent sibling selector (+)
general sibling selector (~)
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