prompt 1:
write a web page in html and css.
graphical components:
- button1: green round start button.
- button2: red square finish button.
graphical component placement:
- button1: top left.
- button2: under button1.
navigation:
- if the user clicks on button1, the background color of the page changes to blue
- if the user clicks on button2, the background color of the page changes to red
