Here's a breakdown:
* Que pases un lindo día: This means "Have a beautiful day".
* Besitos: This is the diminutive form of "besos" which means "kisses". It's a more affectionate and playful way of saying "kisses".
This phrase is a common way to end a message or conversation with someone close to you. It expresses a warm wish for them to have a good day and adds a touch of sweetness and affection.