Responsive Navigation & Pricing Styling

Responsive Navigation - bar on left that opens on most of the screen
once clicked. User clicks out to exit.
Responsive Design - removes the stylesheet controlling the header when
the screen gets too small or the DPI is higher. Currently, no designs
override the header for the mobile version.
Pricing Styling - styled with a 3 column layout. Removed the <dl> and
replaced with <div class="plan"> to accomodate the 3 column layout. <dl>
is hard to make into a 3 column layout let alone responsive.