Help Please!

Does anyone know what the right and left borders on the blog template are called in html? I figured the reason my "spell with flickr" entry turned vertical was because the space for it wasn't wide enough. (It looked fine in the preview.) I tried changing every width or padding or margin I could find in the html code, and nothing affected those exasperatingly wide sides. Some of the changes did eliminate the sidebar image and log, but that was not what I was going for!