You keep insisting that a liturgical day runs from midnight to midnight, and you do this by quoting the very norms that show that a liturgical day sometimes begins at midnight and sometimes begins in the evening…It’s been quite puzzling to me.
Reading your last few posts, I finally realized the issue.
You don’t understand what the term “liturgical day” actually means.
You keep trying to defend something without first understanding it.
The term “liturgical day” refers to that period of time (approximately one day, but sometimes as long as 8 calendar days) in which the Church celebrates a given feast or other commemoration.
The time-period of a liturgical day does not always match with a calendar day because it does not need to match, and indeed sometimes it should not do so.
Realizing that the two kinds of days do not always correspond, the Church uses the term “liturgical day” to distinguish that time-period from a day as it appears in the calendar (ie midnight to midnight).
At first, I thought you were just denying that such a thing as a liturgical day exists, but re-reading your posts here made me realize that the real issue is that you don’t understand what the term itself means.