How to affect color on hover of SVG icons?

Question

css

Hello.
Help solve the problem.
It is necessary to change the color of the icon on hover, the "youtube" icon.
As I don’t play with the code (I’ve already spent 3 hours), nothing works, or you can see a little, or everything floods.
Help please.
Attached the code.
Thanks

Answer 1

It looks like the svg is broken - at the very end of the code there is a layer with a rectangle (rect), which covers all other shapes.