Docu or Hack of layout in Grid

The layout of fields in a grid, in respect of distance to next field, is somehow irregular. To understand more it would be helpful to understand the coding.

I know that with a html analyser I could try to do it myself. Still, having some basic ideas would be of help.

Who has access to such information?

Did you try to customize the grid’s appereance using Layout \ CSS Applications (Themes)?