Not even a few KB of CSS. A single small line is sufficient: pre{font-size:20pt;display:none}:target{display:block} However this CSS needs each board stat

Not even a few KB of CSS. A single small line is sufficient: pre{font-size:20pt;display:none}:target{display:block} However this CSS needs each board state to be in its own <pre> element, which makes the file a bit larger in total (598KB) Here is the result: https://pablo.rauzy.name/dev/prettty.html https://pablo.rauzy.name/dev/prettty.html