Where do I define table width in RHStyleMapping CSS?

Hi

I am creating a settings file (ISF) for importing FM book into RH. When I create a left-aligned table style, I noticed that the table is on the left side, with too much gap on the right. 

I checked the HTML code and saw that the width is set to 622. I changed that to 100% and the table got resized properly.

Now, my question is where do I define that 100% in the style properties/ CSS? Is this 622 coming from FM? If yes, any idea where? I checked the FM style and did not see anything relevant there also.

Thanks for your help.

Sreekanth