I wrote down 1:45, it accepted that as a typo even though the correct one is 00:45 or 12:45.
Duolingo's typo algorithm does all kinds of weird stuff.
This sounds strange. tri is three and ctvrte something with "four" ( one fourth is a quarter ).
Yup. It is three quarters. "It is three quarters towards one". In other words 12:45
Ah, like three quarters towards one? I am not used to count that way.
"towards" probably is not the best translation of "na" but I believe it explains the concept that Czech uses to say time.
I would use the reasoning "It is three quarters (of minutes) on/ in relation to/ being near to .. the next hour, which will be one o'clock" rather sofisticate but that's the only way I could illustrate this .