Applying this to WP?

It is all done through a Cascading Style Sheet (.css) located at:
https://tunevibez.com/presenters/page.css
I don’t know if they hand generated it, or used some software.

Here is a sample:

#andrew a {
    display:block;
    width: 160px;
    height: 160px;
    background: url(images/andrew-rollover.png) no-repeat 0 0;
	border:none;
}

#andrew a:hover {
        background: url(images/andrew-rollover.png) no-repeat 0 -160px;
}

Ok. Where would I place that piece of code then? With WP CSS obv there are different areas so which part?

OK here is what I have built from this. How would I implement this into a normal blank WP page? I need to know where in the CSS I would put this!

#yoshitomario a {
    display:block;
    width: 88px;
    height: 88px;
    background: url

(https://i4.ytimg.com/i/kAgkQjXoYUhAY5mJzjjCiA/1.jpg?v=90cb64) no-

repeat 0 0;
	border:none;
}

#yoshitomario a:hover {
        background: url(https://i47.tinypic.com/5owly9.png) no-repeat 0 

-160px;
}

Oh and finally, once implemented, how do I apply those rules to the HTML/image I want it applied to?

Please someone help I need this to be fixed really soon!

CSS is a big topic. Best place to start reading is here:
https://codex.www.ads-software.com/CSS