The :active CSS pseudo-class matches when an element is being activated by the user. It allows the page to give a feedback that the activation has been detected by the browser. When interacting with a mouse, this is typically the time between the user presses the mouse button and releases it. The :active pseudo-class is also typically matched when using the keyboard tab key. It is frequently used on <a> and <button> HTML elements, but may not be limited to just those.
This style may be overridden by any other link-related pseudo-classes, that is :link, :hover, and :visited, appearing in subsequent rules. In order to style appropriately links, you need to put the :active rule after all the other link-related rules, as defined by the LVHA-order: :link — :visited — :hover — :active.
Note: On systems with multi-button mice, CSS 3 specifies that the :active pseudo-class must only apply to the primary button; on right-handed mice, this is typically the leftmost button.
<h1>:active CSS selector example</h1>
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