Added padding-top to .row rule. Added content and video to Mighty Marks
page. Added external.css page to css folder for external pages to link
to. Changed base.css to external.css in external pages indexes. Added
../ in front of css links in indexes. Added <section> to Mighty Marks
html. In external.css: Added text transform, font size, and font family
to h1. Added font size and font family to h2