/* Elderberry homepage (public/index.html): card shelves.
Phone first. A plum band carries the question and the postcode search; below
it every subject is a shelf of cards. On phones a shelf is a scroll-snap row
with the next card peeking and an "n of N" counter; from 600px it becomes a
grid. White cards are navigation, tinted tiles are content, plum bands carry
the search and the record. The shared header and footer stay in the page's
inline