Combining :after and :hover for Dynamic List Styling

In CSS, combining pseudo-elements like :after with hover states can enhance the visual impact of list items. Suppose you have a list where selected items display an arrow shape using :after. To achieve a similar effect for items being hovered over, follow these steps:

The provided CSS code defines a styled list, with a default style for all list items (#alertlist li), a modified style for selected items (#alertlist li.selected), and a style for items being hovered over (#alertlist li:hover).

To combine :after with the :hover selector, append :after to #alertlist li:hover just as you do with #alertlist li.selected:

#alertlist li.selected:after, #alertlist li:hover:after {
    position:absolute;
    top: 0;
    right:-10px;
    bottom:0;

    border-top: 10px solid transparent;
    border-bottom: 10px solid transparent;
    border-left: 10px solid #303030;
    content: "";
}

By combining the :after pseudo-element with both the .selected and :hover selectors, you can effortlessly apply the arrow shape to both selected and hovered list items, creating a dynamic and engaging visual cue.