Does Blueprint CSS have some standard dimensions, such as 24 columns and 40 pixel width, or 20 columns and 48 pixel width?

Question

and is there usually a file that specifies the specifics of the blueprint settings?

Answer 1

The official quick start tutorial details out the dimensions as:

By default, the grid is 950px wide, with 24 columns spanning 30px, and a 10px margin between columns.

There's also BlueCalc which allows you to generate your own grid.css file with specific column widths, gutters, etc.

The column widths are can also be modified manually by modifying the grid.css file in the BlueprintCSS package. The span-1 to span-24 classes each have an absolute width set (though using BlueCalc is a bit easier to visually see the changes you are making).