Check out example codes for "css how to add hover effect". It will help you in understanding the concepts better.

Code Example 1

/* Changes an element's color on hover */

.selector {
	background-color: black;
}

.selector:hover {
	background-color: blue;
}

Code Example 2

a:hover {
  background-color: yellow;
}

Code Example 3

a:hover
 { 

   background-color: yellow;

 }

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