This is China's version of the Korean drama: Splash Splash Love. Instead of entering the timeslip through a puddle, she enters through a toilet, somehow.

She doesn't have the intelligence of the FL in "Splash Splash Love", unfortunately. I doubt if she could solve those math equations, for example. However, she is somewhat charming in her strong will and her loyalty to her friends, which should be a minor detail, but in C dramaland, this can't be taken for granted of any FL.

This FL trips over herself every few steps though, which became pretty annoying, but overall, she had a mind of her own and was outspoken, not like many human doormat female characters.

The ML, well, he didn't really need to act much, he was just there for show. I don't remember who played the SML, but I do remember I liked him better. If the FL didn't act like a typical teenager (and that smart phone charm was ugly and tacky, and just expressed her lack of taste very well).

The story started out quite strong. The time-travel toilet was a funny and cute idea, had the writers committed to it. Unfortunately, the writers committed the worst storyline crime of all, and went with the "everything was just a dream" route, which is the laziest, most non-committal storyline choice you can possible choose!! Don't waste your time. This could have just been a charming and fun tale, but the writers completely ruined it.