I have an array like this where an object is inside nested arrays:

I have an array like this where an object is inside nested arrays:

I have an array like this where an object is inside nested arrays:

I have an array like this where an object is inside nested arrays:

I have an array like this where an object is inside nested arrays:

Each item of this array is some number:

This question already has answers here: How can I remove a specific item from an array in JavaScript? (150 answers) Closed 19 mins ago. This post was edited and submitted for review 10 mins ago. In an array I want to find the index of a value and then remove that value. The constraint is […]

brief summary of question is

I tried to create a function that will change the background-color of all class-list items whenever a span of the specified className is hovered over.

My problem is as follow, and is more about maths than programming I think. JavaScript is used here.
I have 3 arrays, let’s say :