Finally I worked out how to replace my tables within tables with css on my website.

My normal approach is: surround myself with library books with colourful screen shots, ignore them, proceed using trial and error and slight familiarity, feel frustrated at the unpredictability of results, spend daily train journeys on it, forget which file is the most up to date. But suddenly, everything comes together and the end result is a much neater clever layout that stays centred, where the content doesn’t splay sideways at the slightest opportunity…