You should try to address the latitude issue. (Says the guy who has only to spend a few seconds typing that.)

done

Hey! nice little useful web page. I like the minimalism of it.

Does the math fail because of not considering (i) equation of time and (ii) oblateness of the Earth ?

because mathematically a day can have more than 24h daylight and less than 0

fixed it

Got it. Will happen whenever the latitude is complement of the declination.

Thanks for replying.