We've seen that a web Page is composed of elements — headings, paragraphs of text, images, buttons, and so on — and that you can listen for events that happen to these elements. For example, you could add a listener to a button, and it will run when the user clicks the button....blocks Next We've seen that a web page is composed of elements — headings...parent element Consider a web page like this: html <div id="container">...