'math.DS', 'math.FA', 'math.GM', 'math.GN', 'math.GR', 'math.GT', 'math.HO', 'math.IT', 'math.KT', 'math.LO', 'math.MG', 'math.MP', 'math.NA', 'math.NT', 'math.OA', 'math.OC', 'math.PR', 'math.QA', 'math.RA', 'math.RT', 'math.SG', 'math.SP', ...
That's basically what the '' value is for in your grid column and width definitions. But its not percent, exactly. Think of it as number of pieces of the pie. If one column is 3 and one is 4* that's a total of 7* total width. The first column will be 3/7 of the total. ...