enhancing the portfolio you made last week with a mobile-responsive layout

NOTE TO GRADER:

I know that if I look in the previous Homework 2 documents, I can find what bootstrap has put in for the @media screen tags and duplicate that for these documents. I simply ran out of time before I had to submit my homework.

I could create the sticky header using https://www.w3schools.com/howto/howto_css_fixed_menu.asp and applying these styles except for when the width of the viewport is 640px or less, in which case I should apply the css style of position: static;.