Show / Hide from viewport in/out

How can I have a series of sticky items (videos, text, buttons) appear when a certain grid row content is on screen and disappear when off, no matter what direction the scroll?

Wix Studio Editor

Illuminated Buttons
When the user enters one of the sections (grid row), its corresponding button should change color to match the section text. When they leave a section, that button should go back to normal.

HIdden Pinned Buttons
There are Buttons that correspond to each section (row) that sit in the same location. They should appear when a section/row is entered and disappear when it is left.

Background videos
Each section (row) has its own looping video. Videos should never scroll, they are sticky to the top and should fade in and out according to their section (row).

What have you already tried:
I have tried using the AI in Velo to write code. I have had others try to help and Have looked at a lot of videos and tutorials. I’ve tried “OnViewportEnter” and “OnViewportLeave” and have only had success on downward scrolling, not upward scrolling.

Additional information:
I understand logic, but don’t know code.