CSS: The Definitive Guide, 4th Edition

Chapter 14. Table Layout in CSS

You may have glanced at that title and wondered, “Table layout? Isn’t that exactly what we’re trying to avoid doing?” Indeed so, but this chapter is not about using tables for layout. Instead, it’s about the ways that tables themselves are laid out by CSS, which is a far more complicated affair than it might first appear.

Tables are unusual, compared to the rest of document layout. Until flexbox and grid came along, tables alone possessed the unique ability to associate element sizes with other elements—for example, all the cells in a row have the same height, no matter how much or how little content each individual cell might contain. The same is true for the widths of cells that share a column. Cells that adjoin can share a border, even if the two cells have very different border styles. As we’ll see, these abilities are purchased at the expense of a great many behaviors and rules—many of them rooted deep in the past—that apply to tables, and only tables.

Table Formatting

Before we can start to worry about how cell borders are drawn and tables sized, we need to delve into the fundamental ways in which tables are assembled, and the ways that elements within a table are related. This is referred to as table formatting, and it is quite distinct from table layout: the layout is possible only after the formatting has been completed.

Visually Arranging a Table

The first thing to understand is how CSS defines the arrangement of tables. While this knowledge ...