How to use the style used in XI3.1 in Bi4.1 environments

Hi All,

I am using BI4.1 sp4 patch1 environment and when opening a XI3.1 report in BI4.1, I can see the report format is not getting disturbed but my requirement is that I have to create a few reports in BI4.1 with same format.
Is it possible to import the style used for those report(s) from some where or take from file location and adapt the "WebIDefaultStyleSheet.css" so that all new reports will have the same style.

Thanks in advance,
Sravan.