Sticky Element inside Fixed Background

Hello I have a Fixed Background, and all my images are scrolled in front of the fixed background. Between 2 images, I would like to put a title with a sticky position, and when the title is in the middle of the page I want it to have a fixed position. But I want that the title stays here when the next images are scrolled, and I don’t know how it is possible, can someone help me ? thank you

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