body margins/padding Dixi

Hi there

Could someone guide me to the exact file and code to adjust the margins for the body/content text of my blog? I want to text and images from each blog post to have a good amount of white space on either side of it. As it stands, the prefered post width is set at 505, but my images are set at 460. I'd like the text to also be about 460-470, with the other 35-45 taken up equally by margins on the left and right. I hope this makes sense! :slight_smile:

Thank you