/* Puts the "js" class on <html>, and nothing else.

   Every rule that hides something — the scroll reveals, the loader, the first
   paint of the page — is written behind that class. Loading this file in the
   <head>, before the stylesheet paints, is what stops the page flashing its
   final state for one frame before the animations start.

   With scripts off the class never lands, so nothing is ever hidden. */
document.documentElement.classList.add('js');
