The CSS pseudo class selector :hover is a key component when working with CSS effects. The :hover is used as a trigger to activate a CSS effect. When somebody mouses over an element that has been assigned a :hover selector it starts the CSS settings of the :hover. This provides a new presentation of the element as long as the mouse hovers over the element. Remember that once the mouse leaves the element, no longer hovering, the CSS properties return to their beginning values. Please take a few minutes and research and review the :hover selector in CSS. You will use this a lot when working with CSS.
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