DOM-Manipulation

This code responds to several events:

• Clicking the "Add Item" button adds a new item to the list.
  
• Pressing Enter in a text box also adds a new item to the list.
  
• Double-clicking on a list item removes the last item from the list.
  
• Clicking on a list item changes its style on the page.
  
• Entering text into the text box changes the text of the last item on the page.