Tasks

- add a division tag

- embed a paragraph tag

- insert some text

- apply a span tag to a phrase

- embed a style tag

- set text style for the body element

- set text alignment for the division element

- set text size for the paragraph element

- set background color for the span element

- insert a button element outside the division

- assign a behavior to the button
   ... when the button is clicked 
       the background color of the
       span element changes.