Created mobile-vstack, desktop-horiontal(side by side) view

However, plagued by issues - STL too big on mobile so have to scroll
down for DXF; DXF zoomed in way too much on desktop; and it all changes
by the model (e.g. stool vs catamaran). Recommend investigating
svgpan.js and see if it's interfering with calculation of div size for
stl, which changes after page load = the hardcoded *1.15 fix in
design_comp.js