You can use CSS :hover pseudo-class selector, to create a an attractive  rollover effect—when a user holds their cursor over the button, it displays in a different way. Using the list navigation example from the article How to use a structural list as a navigation menu with CSS, you can add the next CSS line in test.css file:

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#navigation li a:hover {

background-color: #2E2E2E;

color: #FFFFFF;

}

The next picture shows the result:

Creation of rollover navigation with CSS

Creation of rollover navigation with CSS