How do you find the closest ancestor element that matches a specific selector?
element.closest('.selector') finds the closest ancestor element (including the element itself) that matches the specified selector. This method traverses up the DOM tree from the current element, testing each ancestor until it finds a match or reaches the document root. It's especially useful for event delegation scenarios where you need to find a specific parent container from an event target. Unlike parentElement which only goes up one level, closest() will continue searching up the tree until it finds a match.