pub const CELL_WIDTH_CLASSES: &[&str];Expand description
Every class width_class can return, including the
fallback.
See ROW_PART_CLASSES for why it is written out. Only two of the three
carry a rule – a fill is what a cell does when the sheet says nothing –
which is exactly why the list is here rather than being read off the
generated CSS: cell-fill reached every table in the tree and the
vocabulary named it nowhere.