I know that this should be very easy, but I can't seem to find the answer searching the docs or the discussions. Sorry.

How do I limit the width of input boxes in codes such as below? I only want each box to be about 4 characters wide.

FormPage[{"x1" -> "Number", "x2" -> "Number", "x3" -> "Number",  "y1" -> "Number", "y2" -> "Number", "y3" -> "Number"}, fn, 
 FormLayoutFunction -> Function[Grid[
    {{"dependent", #["x1", "Control"], #["x2", "Control"], #["x3",  "Control"]},
     {"independent", #["y1", "Control"], #["y2", "Control"], #["y3",   "Control"]}}]]]

Currently it looks like this:

Thanks in advance,

Mark Greenberg