Chinese sentimentality. The plot has minor sci-fi and fantasy elements, but these are just excuses to set up a romantic film with lighter drama and comedy influences. It's all very glossy, with a strong push for retro appeal, and a vibe that is construed to appeal to as many people as possible.
When Jia's mother is involved in a near-fatal accident, Jia feels bad for never treating her mother the way she deserved. She is then magically transported back into time and lands in 1981, where she meets a younger version of her mom. Jia vows to help her mom attain a better life.
The cinematography is bright and colorful, but also very safe and predictable. The performances are a bit overdone, the romance doesn't really work, and two hours is a bit much. It is easy entertainment though, and it never got too boring, thanks to the somewhat unusual setup.