Seeking a time-travel novel

The female protagonist went out to play and fell into a pit. She seemed to be called Xiao Yu. The small bag that fell down had many things and saved the dying male protagonist. The male lead was a prince who was disliked by the royal family. He had a twin brother, but the younger brother was very popular. The male protagonist was adopted by the Night Palace. Later, he massacred the Night Palace and became the palace lord. In the end, he became the emperor. However, she was poisoned by the red lotus. The people around the male protagonist told the female protagonist that the Empress could enter the secret room of the palace. There was a treasure inside that could save the male protagonist. It just so happened that the female protagonist had transmigrated and was treated as the second miss of some manor. That second miss had previously been madly in love with the male protagonist's younger brother, so she married him. The day of their wedding was the day when the male protagonist's poison acted up. The female protagonist secretly went to see the male protagonist and hardened her heart to save him.

Answer 1

What was the name of the romantic time-travel novel that traveled back to ancient times? I forgot. I only remember a very classic plot in it. The male protagonist was a very intelligent person who traveled back to ancient times and used his modern knowledge to make a name for himself in ancient society. The female lead was a gentle and beautiful woman who met the male lead and had a sincere love story between them.