I would suggest you to use fireBug for checking the styling if documentation css list for component not usable for you.
If I mention the width of the column with percentage ( width=80%) it is not considering. It is take the default width like 100px. If i mention with px it will work, but i wan't to do with percentage.(In order to satisfy different screen resolutions.)
How can i override the default style provided by richfaces to the extendedDataTable.
If we mention theextendedDataTable and columns with px.. It works fine. It is giving problem if i mention with %