Mobile tweaks Pt. 1

Better padding and alignment for all sections.
#hello goes centered and switches to "Learn More" based on user feedback
#work shows more projects in less space. Also fixes the bug where images
weren't always centered.
#toolbox switches to a horizontal layout for small screens
wrong snap point

We don't switch layouts until md
Fix header snap points for SM screens

Birds were mis-aligned
#work center-aligned on phones
#work gallery tightened up for phones

Shrink the padding separating gallery items