Midnight is the first one – It’s the very first second of the day, not the last.
var todayDateTime = DateTime.Today;
var Midnight = todayDateTime.AddSeconds(-1);
//Here are the results
Console.WriteLine($"Today {todayDateTime.ToString()}, Mid night {Midnight.ToString()}");
The output is this;
Today 10/8/2021 12:00:00 AM, Mid night 10/7/2021 11:59:59 PM
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