only affix the sidenav in the docs if the viewport is >800px tall
only affix the sidenav in the docs if the viewport is >800px tall

BS3 commit bb059f28dea0463f44f265ad8f924d3cb508aa42

up2vs/todc-bootstrap,2947721120/googlebt4,todc/todc-bootstrap,todc/todc-bootstrap,ztx1491/todc-bootstrap,todc/todc-bootstrap,mozillo/todc-bootstrap,2947721120/todc-bootstrap,aaroncnhk/todc-bootstrap