What is the ruling on love between a man and a woman before marriage in Islam, and what is its evidence from the Qur’an and Sunnah?

Unintended love between a man and a woman does not entail legal rulings except in terms of chastity. It is permissible to look at the face and hands of the fiancée without lust, according to the Prophet, peace and blessings be upon him, who said: "If one of you proposes to a woman, and he is able to look at what would encourage him to marry her, let him do so." It is forbidden to look at any other part of her body, or to be alone with her, or to touch her body, due to the Almighty's saying: "Say to the believing men that they cast down their gaze and guard their private parts" [Quran 24:30], and the Prophet's saying, peace and blessings be upon him: "Beware of entering upon women," and "No man is alone with a woman but Satan is the third of them," and "For one of you to be stabbed in the head with an iron needle is better for him than to touch a woman who is not lawful for him."