This page gives information about syntax of available TF2 Wiki table styles. This is not a complete guide for using wiki-tables, for that please see Wikipedias table help.
As you can see, the default style includes the TF2 Wiki colors but does not include cell borders or header styles. This is a design feature which allows them to be flexible and extensible enough to apply different styles depending on the users preference.
Borders
There are four typical ways of applying (or removing) cell borders, the easiest (and preferred) method is to add a "grid" to the css class -
The default styling for a table header is to be bold but not have any specific colors applied. To apply the standard TF2 Wiki table header color, a class="header" will need to be specified to each element.
Several CSS style extensions are available that while not specific to tables, maybe useful is specific table uses (nested tables for example). These are applied by including them within the class parameter, as demonstrated in the "grid" parameter above.
transparent
Allows the background layer to show through the table cells (including graphics).
nowrap
Forces the text to display as one line rather than wrapping round when whitespace characters occur.