How do you make an element change when it touches another element

Question

it can be a moving object like a moving button and when it touches another one it changes its properties like color

Answer 1

you need collision testing

https://code.sololearn.com/W84hbYz246Pn/?ref=app
https://code.sololearn.com/Wm4CueXKHCxw/?ref=app

Answer 2

You can handle the (location) .. x,y

By if & ==
.....

Because they will only touch when the first location approaches the second